

















































































































































































































































































































































































































































































































































































































































































































































































































































/ 


59th Congress, | 

1st Session. j 


SENATE. 


j Document 

) No. 264. ; 


5~3TT\ Q.crwor , ^ l'bV t y )0O £ v !9c)(^ , 


DOCUMENTS 


RELATING TO THE 


INTEROCEANIC CANAL 


AND 


A LETTER FROM THE SECRETARY OF STATE 
TRANSMITTING CERTAIN INFOR¬ 
MATION IN REGARD TO 

THE EARTHQUAKE AT PANAMA 

IN 1882. 


March 12, 1906.—Referred to the 
Committee on Interoceanic Canals 
and ordered to be printed as one 
document. 


WASHINGTON: 

GOVERNMENT PRINTING OFFICE. 

»»» *• > . >» 

1906. ; o 













In the Senate of the United States, 

May 15 , 1902. 

Ordered , That the following documents, heretofore printed, bp reprinted and bound 
in one document for the use of the Senate, namely: 1. The report of the Nicaragua 
Canal Commission of May 9, 1899, without appendices. 2. Chapter VII of the report 
of the Isthmian Canal Commission of November 30, 1901. 3. The letter of Maj. 

E. C. Dutton of June 22, 1891. printed in Report No. 2126. made to the House of 
Representatives, first session, Fifty-fourth Congress. 4. And the chapters on 
“Earthquakes,” pages 132 to 136, and on “Seismic Records of the Canal Region,” 
pages 136 to 137 of Appendix 2 of the report of E. S. Wheeler, chief engineer of the 
Nicaragua Canal Commission. 

Attest: 


2 


Charles G. Bennett, Secretary , 
By H. M. Rose, Chief Clerk. 


i 


U 5 IS06 

0. of D. 



[Senate Document No. 357, Fifty-seventh Congress, first session.] 


3 

O 

vh 

r> 


v 



£ REPORT OF THE NICARAGUA CANAL 

COMMISSION. 

9 


Washington, D. C., May 9 , 1899. 
The President of the United States. 

Sir: The Nicaragua Canal Commission, having completed its labors, 
has the honor to report as follows: 

The Commission was organized July 29, 1897, and its first meeting 
was held on that day. It consisted of Rear-Admiral John G. Walker, 
United States Navy, president; Capt. O. M. Carter, United States Corps 
of Engineers, and Prof. Lewis M. Haupt, civil engineer, members. 
Captain Carter was relieved from duty with the Commission and was 
succeeded on October 18 by Col. Peter C. Hains, United States Corps 
of Engineers. 

This Commission has understood the law, approved June 4,1897, by 
which it was constituted, to require that all routes heretofore proposed, 
having any merit, should be considered; new routes that appear to have 
merit should be developed; and the entire region of canal possibilities 
should be examined with sufficient thoroughness to enable a just and 
comprehensive comparison of the various routes to be made and the 
most desirable one selected; in short, to enable it to make a complete 
and exhaustive report. 

With this in view the Commission established its headquarters in the 
Army Building, in New York, and devoted considerable time to a care¬ 
ful examination and study of all data bearing upon the Nicaragua Canal 
question obtainable in the United States, including Government sur¬ 
veys and surveys by private parties, going back nearly fifty years. 
During this time an engineering staff was engaged, and the organiza¬ 
tion of exploring, surveying, geological, and Irydrographic parties was 
proceeded with, considerable delay being caused by the necessity for 
a change of engineer members of the Commission. A commissary 
department was also organized for the handling of supplies and food 
from the United States, as it was impossible to supply the large force 
employed with promptness and certainty from the resources of Nica¬ 
ragua in the wild part of the country where the work was prosecuted. 

The preliminary studies having been made and the organization com¬ 
pleted, the expedition sailed from New York on the U. S. S. Newport 
on December 5,1897, nearly one hundred strong, and arrived off Grey- 
town December 17. The men and stores were landed as promptly as 
possible, and as fast as laborers could be engaged the various parties 
were put into the field and entered upon the work assigned them. 

3 



4 


INTEROCEANIC CANAL. 


Through the courtesy of the Secretary of the Navy, the U. S. S. 
Newport was assigned to the service of the Commission for the survey 
of Grey town Harbor and vicinity, the IT. S. S. Alert for the survey of 
Brito and its vicinity, and a strong hydrographic party under Lieutenant 
Hanus, of the Navy, was assigned to the survey of Lake Nicaragua and 
the San Juan River. 

The following instructions for the guidance of the chief engineer of 
the Commission were issued December 21, 1897: 


San Juan del Norte, Nicaragua, 

December 21, 1897. 


Mr. E. S. Wheeler, C. E., 

Chief Engineer to the Nicaragua Canal Commission. 

Sir: The Nicaragua Canal Commission, appointed by the President under the act 
approved June 4, 1897, has selected you to take charge of the field work and direct 
the operations of the various parties to make the surveys and examinations provided 
for in the act above referred to in reference to the Nicaragua Canal. 

The scope and character of the work are indicated by the words of the law, “to 
continue the surveys and examinations * * * into the proper route, the feasibility 
and cost of construction of the Nicaragua Canal, with the view of making complete 
plans for the entire work of construction of said canal as therein provided.” 

Your familiarity with the methods employed in conducting surveys and examina¬ 
tions under the Government with a view to projecting works of improvement renders 
it unnecessary at this time for the Commission to give you other than general instruc¬ 
tions. The details and methods the Commission leaves to you to work out as you 
find best and as circumstances render advisable, the field parties being directly under 
your orders. The Commission desires as a final result'to be in possession of all the 
physical data which bear in any important way upon the construction of the Nica¬ 
ragua Canal, and it is expected that the accuracy and trustworthiness of these results 
shall be unquestioned. Due care will be exercised not to unnecessarily duplicate any 
of the accurate work already done. 

Naval hydrographic parties working under the direction of the Commission will 
survey Brito Harbor and vicinity, Greytown Harbor and vicinity, Lake Nicaragua, 
and the San Juan River. All these parties will connect their gauges with the benches 
established by your topographical parties, so that their soundings and your work shall 
conform to the same datum plane. You are expected to confer freely with the chiefs 
of these parties, that you both may have a clear understanding of your mutual work. 

The Commission desires, among other things, that you determine at Greytown and 
Brito the mean sea levels, and connect them, if practicable, with a line* of precise 
levels from ocean to ocean. You will also make such surveys between Brito and Lake 
Nicaragua as may be necessary to locate the best line for the canal, and such other 
investigations as may serve to determine the practicability of controlling the lake 
level by a weir on the west side. 

Borings should be made to ascertain the kind and quantity of material to be 
removed in forming the harbor at each terminus of the canal and along its entire 
route, including the San Juan River. These borings should be made more numer¬ 
ous at the proposed site of locks, sluices, and dams than are necessary elsewhere. 
Particular attention should be given to the Ochoa and other important dams and to 
the San Francisco and San Carlos embankment lines. The feasibility of the canal 
company’s project hinges on the control of the lake level, the Ochoa Dam and, the 
maintenance of the Divide cut. All possible data bearing on these questions should 
be gathered. 

The proper naval hydrographic party will make the necessary survey of Lake 
Nicaragua to determine with sufficient accuracy its area, in order that the question of 
controlling its level may be properly studied, the extent of the available anchorage 
between Ometepe Island and the west shore be ascertained, as well as the safety of 
the course which would be followed by steamers between the western entrance to 
the canal and the head of the San Juan River. 

Where the bends of the river are sharp it may be necessary to cut through them. 
The survey should be made to cover such possible contingency. The disposal of the 
spoils from the excavations in the river must be taken into consideration. These 
should be deposited where they will facilitate rather than interfere with navigation. 

A suitable number of rain and evaporation stations should be established at the 
most desirable points in the drainage basin affecting the canal. The records of these 
should be continued as long as practicable. 


INTEROCEANIC CANAL. 


5 


The low-level line following the San Juan to near its junction with the Colorado 
should also be surveyed, and an estimate of its cost determined for comparison with 
other projects. This line has always been regarded as practicable, and while it has 
considerably greater length than the comparatively direct line through the Divide, 
it will avoid some of the difficult engineering problems of the latter route. 

The survey of the San Juan should also include the gauging of the river at numer¬ 
ous points, the determination of its slope in high and low stages, its discharge in both 
stages, the discharge and regimen of the principal streams that empty into it, and 
generally all information necessary to determine the best method of improving its 
navigation, whether by canalization or otherwise. 

All the field parties will receive their instructions directly from you. It is 
expected, however, that you will keep the Commission fully informed as to the char¬ 
acter of the work being done and the methods adopted by you in doing it. For this 
purpose you will submit monthly reports to the Commission (which shall contain a 
concise history of the operations and progress of the work) and such special reports 
as may from time to time be necessary. These instructions are not intended to be 
final and complete, but may be supplemented by others from time to time as the 
exigencies of the work demand. 

I am, very respectfully, # J. G. Walker, 

President of the Commission. 


The Commission remained in Greytown until January 8, 1898, when 
it proceeded in a special steamer, kindly placed at its disposal by the 
Nicaraguan Government, to the examination of the San Juan River 
from the sea to where it leaves Lake Nicaragua, including the Colo¬ 
rado branch. 

Five daj^s were occupied in this examination. The Commission 
arriving at Fort San Carlos, the head of the San Juan River, on 
the evening of January 13 proceeded at once by steamer to San 
Jorge, where it arrived on the following morning, and after putting 
ashore its equipment, supplies, and extra baggage continued to Gra¬ 
nada and Managua for the purpose of paying its respects to the Presi¬ 
dent of the Republic. 

Arriving at Managua on the afternoon of the 15th of January the 
Commission was specially received by the President at 8 o’clock on the 
same evening with all the ceremonies and honors pertaining to such 
occasions. During its stay in Managua every attention was shown b} r 
the President, members of the cabinet, and other officers of the Gov¬ 
ernment. On the morning of the 18th the Commission called upon the 
President to take formal leave, and then proceeded by rail to Granada, 
w r as transferred to the lake steamer Victoria, and reached San Jorge 
late the same afternoon, arriving at Rivas shortly afterwards, where 
temporary headquarters were established. 

Promptly upon its arrival at Rivas the Commission took up the 
investigation of the canal route from the lake to the Pacific, and 
remained either in Rivas or upon the proposed line of the canal until 
Februaiy 13, having been somewhat delayed by an attempt at a revo¬ 
lution during that period. 

On the 13th the Commission left by steamer for San Carlos, at the 
head of the river San Juan, arriving at that point on the morning of 
the lJth. 

After inspecting the work of the parties under Lieutenant Hanus, 
U. 8. N., and Mr. Stuart, assistant engineer, the Commission, on the 
following morning, proceeded down the river, landing that afternoon 
at Ochoa, and, after examining the work going on in that neighbor¬ 
hood, which included borings at the proposed site of the Ochoa Dam, 
started on foot upon the trail over the Divide for a personal examina¬ 
tion of that part of the line, arriving at Greytown at 6 p. m. on the 21st. 

The Commission remained in Greytown until February 27, when it 


6 


INTEROCEANIC CANAL. 


left on board the U. S. S. Newport for Port Limon, Costa Rica, arriv¬ 
ing- there on the following day, and proceeding by special train, pro¬ 
vided by order of the Costa Rican Government, to the capital (San 
Jose), for the purpose of paying its respects to the President of Costa 
Rica. The Commission was pleasantly received by the President, by 
special appointment, at 8 p. m. March 1. The next day was spent in 
visiting the neighborhood of the capital, leaving San Jose by special 
train on the morning of the 3d for Port Limon, and going immediately 
on board the Newport. During the trip to and from San Jose the 
cuts and embankments along the line of railroad were carefully observed 
with a view to obtaining information with regard to the stability of 
slopes in tropical regions in connection with the proposed canal. 

The Newport sailed at 6 p. m., March 3, for Colon, arriving the fol¬ 
lowing day (March 1). The five succeeding- days were spent in exam¬ 
ining the Panama Canal line,, the work being done, and the plans, 
drawings, and data in the office of the company in Panama. 

In this connection the Commission wishes to express its warmest 
thanks to M. Belin, the director-general, and to the officers of his staff, 
for their kindness and untiring efforts to facilitate its work in every 
way possible, also to Mr. John F. Shaler, the superintendent of the 
Panama Railroad, for his aid, assistance, personal efforts, and care 
during its entire stay upon the Isthmus. 

On the 10th, having taken leave of the officers at Colon, the New¬ 
port sailed for Port Limon and Greytown, arriving at Greytown on 
March 12. 

On March 26 the Commission, having completed its personal exam¬ 
ination of the proposed Nicaragua Canal route, took its departure for 
the United States, leaving its working parties in the field to prosecute 
the work assigned them under the direction of Mr. E. S. Wheeler, its 
chief engineer. 

Much delay to the work and great annoyance to working parties 
were caused by attempts at revolution and by the strained relations 
between the Governments of Nicaragua and Costa Rica, which ren¬ 
dered it difficult and often impossible to forward supplies, provisions, 
and orders to working parties in the field and to receive reports from 
them. It is a difficult country in which to carry on work of the kind 
assigned to this Commission at any time, but the difficulties were 
increased many, fold and great delay was caused by the disturbed con¬ 
ditions referred to. The outbreak of the war between the United 
States and Spain was also a serious matter. It deprived the Commis¬ 
sion of two ships and the naval parties which were working with and 
under its direction, rendering a new organization of parties necessary 
and with a much decreased force. 

Further delay was caused by the assignment of Colonel Hains to 
military duty in command of troops at Chickamauga, and later in Porto 
Rico. 

But in spite of these troubles and delays the work was prosecuted 
as rapidly as practicable. 

As portions of the work were completed parties were withdrawn, 
until the last surveying party left Greytown February 18, 1899, leav¬ 
ing thirteen men in the country at ten stations for the purpose of 
continuing the observations for rainfall and evaporation and for the 
gauging of the lake and the various rivers necessary to a complete 


INTEROCEANIC CANAL. 7 

understanding of the hydrology of the region of the country through 
which a canal through Nicaragua must pass. 

Soon after the commission’s arrival home, the necessities of the war 
forced it to vacate its headquarters in the Army Building in New 
York, and they were removed to Washington, where the work of 
examining, computing, and assembling the data has been steadily 
prosecuted. 

The Commission desires to express its obligation to the Maritime 
Canal Company, which kindly and freely furnished all data and infor¬ 
mation in its possession; 

To the Navy Department for assistance with ships, parties, and 
instruments; 

To Commanders Tilley and Leutze, commanding the U. S. S. Newport 
and the U. S. S. Alert , for their excellent surveys of Greytown and 
Brito; 

To the Director of the Geological Survey for the services of C. W. 
Hayes, geologist, and A. P. Davis, hydrographer; 

To the Chief of Engineers and to the Superintendent of the Coast 
Survey for instruments kindly loaned; 

To the Panama Canal Company and the Panama Railroad for aid and 
courtesies rendered; 

To E. S. Wheeler, C. E., chief engineer to the Commission, and to 
the members of the engineering staff for their faithful services in 
connection with the work. 


PHYSICS. 

To secure the best location for the canal careful attention must be 
given to the physical features of the isthmus and their adaptation to 
the purpose. 

As the reports of the specialists, hereto annexed, cover the subjects 
of geology, topography, hydrology, and meteorology quite fully, it 
would seem unnecessary to do more than call attention to a few distinct 
features which characterize the route on which this Commission is 
directed to report. 

LAKE NICARAGUA. 

It is an interesting and peculiar feature of this route that in early 
geologic time the lake was evidently an arm or bay of the Pacific 
Ocean, while the Continental Divide traversed the isthmus to the 
eastward in the vicinity of Castillo Viejo, and the Rio San Juan, as an 
outlet of the lake, had no existence. This is attested by the remains 
of an old river channel of large dimensions, which crossed the Western 
Divide and formed the outlet of the lake after it became separated 
from the ocean, and by other geologic features. 

An old drainage channel is also traceable under the Rio San Juan 
west of Castillo, which has gradually filled up with alluvium to the 
present bed of the stream. There is, therefore, but little rock found 
in this portion of the river. 

In consequence of the closure of the western outlet and the elevation 
of the lake to a mean altitude of over one hundred feet above the sea, 
the outflow was diverted to the eastward over a depression in the 
original divide, so that this river now forms the only outlet for the 
drainage of the entire basin. 


8 


INTEROCEANIC CANAL. 


The physical elements which are of most importance in the consider¬ 
ation of the problem of water supply, lake regulation, storage, and 
operation have been ascertained by observation, surveys, and measure¬ 
ments as far as possible, and may be stated as follows: 

Area of water surface of Lake Nicaragua.2,000,000 acres, 3,000 square miles. 

Approximate area of entire drainage basin.12,900 square miles. 

Maximum dimensions of Lake Nicaragua.101 by 45 miles. 

Elevation of Lake Nicaragua.98 / to 111 7 , mean 104P above mean sea level. 

Elevation of Lake Managua (above Lake Nicaragua), approximately.28 feet. 

Area of Lake Managua.438 square miles. 

Length of Rio San Juan.121.7 miles. 

Extreme range of temperature on line of canal for 1898 (65° to 96°).31 degrees. 

Maximum rainfall observed at Rivas was in 1897, when it was.123.43 inches. 

Minimum rainfall observed at Rivas was in 1890.31.81 inches. 

The average rainfall in the basin for 1898 is found to be 28 per cent less than at Rivas. 

The lake is elliptical in form and has several islands. The principal 
one, containing the symmetrical cones of the extinct volcanoes Ometepe 
and Madera, rises over a mile above the lake level and affords an 
excellent harbor to leeward, convenient for anchorage. Near the out¬ 
let of the lake it shoals to such an extent as to require a considerable 
amount of dredging through soft material. No rock is found near 
this portion of the channel. The area of that portion of the lake 
extending below sea level is about 20 square miles. A steady northeast 
trade sweeps over the lake during a large portion of the year. 

WESTERN DIVISION. 

The lake is separated from the Pacific on the west b} T a strip of land 
about 12 miles wide with a range of hills having heights varying from 
155 feet to more than a mile above sea level. The lowest point has 
been selected for the route of the canal, and is where a low plateau 
separates the drainage of the Rio Lajas, which empties into the lake, 
from the Rio Grande, emptying into the Pacific near Brito head. 
This latter is a bold, rocky promontory 218 feet high, which guards a 
natural bight in the coast and affords an admirable site for an artificial 
entrance and harbor. 

The streams of this section are small and have a limited drainage, 
being nearly dry for five months of the year. The slope of the upper 
Rio Grande, however, is steep and its bed is therefore sinuous and 
deeply eroded. Between Espinal and the sea, a distance of less than 
11 miles, it falls about 120 feet. The topography of the vallej^ is, how¬ 
ever, well adapted to the purposes of a canal on either bank, or to the 
creation of an artificial basin by a dam closing the gorge through which 
the lake drainage formerly passed to the sea. The rocks on this divi¬ 
sion are sedimentary and readily worked, being loose shales and sand¬ 
stones with traces of calcium. The material composing the coastal 
plain is a light sandy loam and easily eroded. 

EASTERN DIVISION. 

The country traversed by the San Juan may be conveniently divided 
into two sections, to wit, that portion lying above the confluence with 
the San Carlos, in which the deposit of sediment is relatively small, 
and that below, in which it is large. Further subdivisions are sug¬ 
gested by the topographic conditions. From the lake to the first rapids 
at Toro, 27 miles, the slope is gentle, being about 2^ inches per mile, 












INTEROCEANIC CANAL. 


9 


while the banks are low and the adjacent swamps extensive. From 
the head of the Toro to the foot of the Machuca, embracing the four 
rapids, the fall is nearty 43 feet in 23 miles, or 22^- inches per mile. 
This, comprises the rocky section of the ancient Continental Divide 
and is the gorge of the river valley. Below Machuca occurs a stretch 
of about 15 miles of deep water, the bottom of which extends in places 
to below sea level, known as the Agua Muerta (dead water). This is 
a portion of the old river channel not silted up by the volcanic sands 
brought into the lower San Juan by the San Carlos River. This sand 
becomes a characteristic feature of the entire lower reach of the river 
and its delta from this point to the sea. It is confined, however, 
mainly to the bed of the channel, the banks through the hill country 
being the stiff clays resulting from the weathering of the rocks of the 
region. These banks are remarkably stable, notwithstanding the heavy 
rains and large volume of water which sweeps past their bases at high 
stages. 


PHYSICS OF THE STREAM. 

As the bed of the upper river forms an important part of the route, 
a more detailed description of it is believed to be necessary. 

The slope as given by the survey and corrected for stage may be 
stated to best advantage in tabular form. This, taken with the cross 
sections, velocity, and volume of discharge as stated in detail in the 
accompanying report, of the assistants will show the characteristics of 
the streams in a state of nature. 

San Juan River statistics—slopes and distances. 

UPPER RIVER. 

[Lake at 105.] 


Reach. 

Distance. 

Fall. 

Rate of 
fall per 
mile. 

From the lake t,o Sa,halos. 

Miles. 
27.16 

Feet. 

5.4 

Feet. 

0.198 

Sa halos to foot of Toro rapids. 

1.70 

7.3 

4.294 

Toro to head of Castillo. 

7.98 

1.2 

.150 

Cfl.st.illo to bottom of rapids .. 

.38 

.0 

15. 789 

■Rnttnm of Castillo ra.nids to Pnnta Cord a . 

2.08 

2.5 

1.202 

Pnnta C-orda to 1 mile below Ma.ehnea. rapids. 

10. 62 

26.0 

2.448 

Onp milp hplow Map.hnoa rarvids to Rooa San Carlos. 

14.79 

1.0 

.067 


TTrmer river..... 

64.71 

49.4 

.763 



LOWER RIVER. 


Hop a £an Carlos to San .Tnanil lo ..... 

33.02 

5.28 

18.65 

30.0 

4 0 
21.0 

ftan Tnanil In to Colorado ...-. 


T.nlrp to sea, .- -.... 

121. 66 

104.4 



The slopes are, however, constantly varying with the stage and local 
conditions. In fact, a heavy rainfall on the San Carlos Basin may 
reverse the slope for a time in the Agua Muerta, causing the water to 
run up stream. 







































10 


INTEROCEANIC CANAL. 


At Sabalos, where the slope is about 2£ inches per mile, the maxi¬ 
mum velocities and discharges as observed were reported as follows: 


Date. 

Cross section, 
(square feet). 

Mean velo¬ 
city (feet 
per second). 

Discharge 
(cubic feet 
per second). 

January 21,1898. 

8,819 
8,576 
11,273 
10,684 
10, 720 

2.16 

19,000 
16,530 

February 21,1898 . 

1.92 

September 11, 1898. 

1.95 

21'995 

September 14, leys... 

2.12 

22,6”3 
22,431 
26,700 

September 21,1898. 

2.09 

December 3,1898. 

11,273 

2.39 



In the upper reaches, the slope being very flat, the river carried over 
20,000 cubic feet through sections of over 10,000 square feet at veloci¬ 
ties exceeding 2 feet per second, with corresponding increase at the 
gorges and rapids. 

OBSERVED MAXIMUM VELOCITIES OF SAN JUAN. 

At Ochoa Station, about 69 miles from the lake, the banks are steep 
cla} r slopes The bed of the river consists of black sand of the same 
character as that composing the sea beach near Greytown. 


Date. 

Cross section 
(square feet). 

Mean velo¬ 
city (feet 
per second). 

Discharge 
(cubic feet 
per second). 

January 8,1898. 

13,100 
14,462 
19,717 
10,336 
12, ^61 
9,895 

4.00 
4.25 
5.32 
4.00 
4.47 
4.24 

52,400 
61,410 
104,930 
41,199 
57,047 
41,975 

June 28*, 1898. 

November 17,1898 . 

September 12,1898.. 

September 16,1898. 

September 26,1898. 



From which it appears that in a state of nature the mean velocity of 
the stream is frequently over 1 feet per second and at times exceeding 
5, while the lower river discharges over 50,000 cubic feet per second, 
and occasionally over 100,000, without perceptible effect upon the 
banks. 

The slopes of the stream, therefore, vary from about 1 inch per mile 
in the Agua Muerta to 6 feet in one-third of a mile on the rapids at 
Castillo, and the velocity from less than 1 foot per second to over 12, 
while the recorded discharge of Ochoa ranges from 16,115 to 101,930 
cubic feet per second. To pass the Castillo Rapids at low stages of the 
river a tramway has been constructed under the brow of the hill for 
the purpose of transferring passengers and freight. The width of 
the upper river is quite variable. Its narrowest limits are about 350 
feet, while in some places it widens out to 1,200 feet. Its general 
alignment is direct, but there are several sharp horseshoe curves where 
cut-offs would be required across alluvial fiats by which over 1 miles of 
distance would be saved. 

THE LATERAL DRAINAGE. 

The principal tributaries from the Costa Rican side are the Rio Frio, 
Poco Sol, San Carlos, and Sarapiqui, the former emptying into the 
lake just at the head of the river. These large streams exert a con- 



































INTEROCEANIC CANAL. 


11 


trolling* influence in confining the location of the canal to the left bank. 
The streams on the left bank are the Melchora, Palo de Arco, Negro, 
Sabalos, Machuca, La Cruz, Machado, Danta, San Francisco, and others, 
none of which have a large drainage basin. They have many small 
branches permeating the swamps and ravines which characterize the 
broken topography of this section. 

On reaching the edge of the coastal plain the river drainage is dis¬ 
tributed through the San Juanillo, Colorado, Lower San Juan, Taura, 
and their branches, Parado and Cano Bravo, leading to the sea. 

The minimum computed discharge of the upper river at the Sabalos 
Station during 1898 was found to be 11,206 cubic feet per second on 
May 13, while the maximum occurred on November 13, when it was 
28,490 feet, the difference in stage being 3.55 feet. At Ochoa, below 
the mouth of the San Carlos, the minimum computed discharge on 
May 10 was 16,300, and the maximum was 107,000 cubic feet per sec¬ 
ond on November 17, the variation in stage being 13.35 feet. To pro¬ 
vide for extreme cases, however, it is estimated that the river above 
the San Carlos may, at rare intervals, under the cumulative discharges 
from the lake and river, reach a possible maximum of 100,000 second- 
feet, and that the San Carlos, a flashy and torrential stream, may add 
100,000 more to this quantity in the lower section for a short time. 

THE CAPACITY OF THE CHANNEL. 

The entire river bed has been carefully surveyed with a view to 
determine its carrying capacity under the regimen resulting from the 
creation of such dams and locks as may be found best adapted to 
convert it into a navigable channel for deep-draft vessels. The upper 
river will require dredging from the lake to the Castillo Rapids, and 
as the channel as proposed will he 300 feet wide at bottom and 
extend to a depth of 30 feet below the lowest lake level, this cut will 
largely increase the cross section and thus enable a larger volume to 
be discharged without any material increase of velocity. Moreover, 
the river falls about 13.9 feet below the 105 stage in the lake before 
reaching the head of the Castillo Rapids, so that a dam farther down 
stream impounding this water would still further augment the cross 
section by raising the surface. As the capacity is regulated by the 
smallest sections, it is necessary to ascertain their location and effects 
upon the discharge under the new regimen. 

THE CONTROLLING SECTION. 

Under existing conditions the ruling sections of the stream are 
found to be at stations 1494 and 1515, near the head of the Toro Rap¬ 
ids and Castillo Rapids, in that section of the upper river between Fort 
San Carlos and the Castillo Viejo, as indicated below. The relation 
of the existing cross section of the stream to that of the improved sec¬ 
tion when raised to the upper level of the lake and dredged to the 
requisite depth of 30 feet, with a bottom width of 300 feet, is stated in 
square feet and percentages. 


12 


INTEEOCEANIC CANAL. 


Relative areas at controlling sections. 


Location (station). 

Miles. 

Original 

area 

(square 

feet). 

Enlarged 

area 

(square 

feet). 

Percent¬ 
age of 
increase. 

268. 

5 

7,810 

1 15,200 

94.6 

680 . 

13 

l \ 697 

1 15; 920 
17,200 
21,840 
32,824 

94.0 

1,265 . 

24 

7^960 

116.0 

y 494 . 

28$ 

28$ 

1 2 ,948 
13,758 

641.0 

1 ,515... 

775.0 

L665 . 

311 

Castillo. 


6,435 
6,060 

23,406 
44,370 

264.0 

Lower Machua. 


632.0 




1 Minimum. 


From this it appears that the location of the controlling section 
would be changed from its present position to a point 5 miles from the 
lake, while the area of that section would be very nearly doubled at a 
lake elevation of 110 feet above tide. As the maximum discharge 
required to pass through this section, with a range of 6 feet for the 
greatest fluctuation, would not produce velocities exceeding 3.3 feet 
per second, such a discharge would not materially affect the stabilit}' 
of the channel nor its navigation. A further discussion of the resulting 
velocities under different volumes of discharge is submitted by Mr. F. 
L. Stuart, assistant engineer, showing that at no other place in the 
channel would the A r elocitv be as great. 


Computed velocity in river and canal at various points, with different discharqes, referred 

to lake at 110. 


Location. 


Station 268, in river . 
Station 680, in river . 
Station 1265, in river 


[Surface of water 110.] 

Discharge, Discharge, 

30,000 50,000 

cu. ft. cu. ft. 

Velocity Velocity Various discharges. 

(ft. per sec.).(ft. per sec.). Cu. ft. Vel. Cu. ft. Vel. 

1.16 1.86 62,500 2.4 42,500 1.66 

1.3 2.2 2.8 1.86 


Location. 


In river 
In canal 


Discharge, Discharge, 
30,000 50,000 

cu. ft. cu. ft. 

Velocity Velocity 

(ft. per sec.).(ft. per sec.). 


1.9 

1.9 

1.7 


3.3 

3.1 

2.9 


Various 

discharges 

Velocity 

(cu. ft. 

(ft. per 

per sec.). 

second). 

J55, 000 

3.6 

\35, 000 

2.3 

160, 000 

3.7 

140, 000 

2.5 

)70, 000 

4.1 

\50,000 

2.9 


Jut-off Palo de Arco to Tsla Grande. 


Cut-off Sombrero de Quero to Santa Cruz River. 


[Surface of water 110.] 


Discharge, Discharge, 

30,000 50,000 

Location. cu. ft. cu. ft. 

Velocity Velocity Various discharges. 

(ft. per sec.).(ft. per sec.). Cu. ft. Vel. Cu. ft. Vel. 


In river. 1.4 

In canal, bottom 15.0. 2.3 

In river. 1. 03 

In canal, bottom 250. 1. 9 


2.3 75,000 3.56 50,000 2.3 

4.00 .5.9 .4.0 

1.72 75,000 2.56 50,000 1.72 
3.23 . 4.86 .. 3.23 






































INTEROCEANIC CANAL. 13 

Cut-off 2 miles west of Boca San Carlos. 

[Surface of water 110.] 

Discharge, Discharge, 



Location 

30,000 50,000 

cu. ft. cu. ft. 

Velocity Velocity 

(ft. per sec.). (ft. per sec.). 

Various discharges. 
Cu. ft. Vel. Cu. ft. 

Vel. 

In river .. 
In canal.. 


. 0.6 1.0 

. 0.7 1.18 

100, 000 2. 01 80, 000 
. 2.36. 

1.6 

1.8 


Location. 


In river 
In canal 


Two dams above cut-off , 8-lock system. 

[Surface of water 82.4.] 

Discharge, Discharge, 

30,000 60,000 

cu. ft. cu. ft. 

Velocity Velocity Various discharges. 

(ft. per sec.), (ft. per sec.). Cu. ft. Vel. Cu. ft. Vel. 

. 0.8 1.35 100,000 2.7 . 

. 1.23 2.1 . 4.1 . 


Two dams above cut-off , 8-lock system. 

[Surface of water 73.2.] 

Discharge, Discharge, 

30,000 50,000 

Location. cu. ft. cu. ft. 

Velocity Velocity Various discharges. 

(ft. per sec.), (ft. per sec.). Cu. ft. Vel. Cu. ft. Vel. 

In river. 0.83 1.39 100,000 2.77 80,000 1.2 

In canal. 1.30 2.17 . 4.33 . 3.45 

This table farther demonstrates that instead of having velocities 
exceeding 12 feet per second over the rapids, which would be sub¬ 
merged, the maximum current in the river under a discharge of 30,000 
cubic feet would not exceed 2 feet or 1£ miles per hour, which would 
not readily disturb the banks of this section of the stream. Under 
ordinary conditions and throughout nearly this entire reach the 
velocities would be less than 1 foot per second. 

With a discharge of 50,000 cubic feet, which is higher than will 
probably ever be reached in this (upper) part of the river, the maxi¬ 
mum velocity through the controlling sections would not therefore 
much exceed 3 feet per second, imposing no material restrictions on 
navigation. 

STABILITY OF SLOPES. 
nature’s compensations. 

So much stress has been laid upon the excessive precipitation and 
its destructive effects upon the proposed works, as well as upon the 
labor and machinery required, that the Commission is impelled to call 
attention to the fact that the physical features of the country furnish 
the most convincing and conclusive evidence that these uncontrolled 
forces are not so injurious as has been alleged, for the angle at which 
freshly made earth slopes stand is found to be much steeper than that 
prevailing in our more northern latitudes, where they are also exposed 
to the destructive action of frost and the internal stress due to greater 
ranges of temperature. In some cases in the northwest the range 
covers 160 degrees, whereas in Nicaragua the greatest fluctuation 















14 


INTEROCEANIC CANAL. 


seldom exceeds 25 degrees. The absence of frost more than compen¬ 
sates for the excessive downpour. 

Observations by engineers of experience in tropical countries lead 
them to believe that the same security and greater permanency may 
be obtained with less first cost and economy of maintenance by making 
the side slopes steeper, and thus reducing the prisms of cut and fill, 
than by employing the typical sections of our own latitudes. Nature 
compensates for the greater rainfall by the uniformity of heat and 
moisture. The spontaneous growth of vegetation revets the natural 
surface, clothing it with a protecting thatch which not only T acts as an 
elastic cushion to break the impact, but also to retain the water and 
thus prevent the sudden and destructive fioods so familiar to us during 
the spring, when the rain and melting snows combine to produce their 
maximum effects. 

The board of 1S95, in referring to the character of the work done 
in Grey town Harbor, remarks that: 

The material excavated was almost entirely volcanic sand, similar to that of the 
beach. * * * When piled in heaps, it forms a porous mass through which the tor¬ 
rential rainfalls descend with surprisingly little effect upon its contour, even though 
the slopes be steep. This feature was noted both in the mounds of dredgings near 
the entrance and in the canal banks, where the sand dropped from the dredge chutes 
still stood, seemingly undisturbed since they were put there. 

Of the cuts along the railroad the board also adds: 

The cuts have heights up to 20 feet, with slopes from vertical to 45 degrees, and in 
most cases stood with an extraordinary stability under the tropical downpours. At 
several the original tool marks were still visible, both picks and steam shovel. 
In several others there had been slides, but none of great extent. The ditches were 
generally clean, and in but few points had wash reached the rail. The surface of the 
cuts was in some cases protected by vines, but in most was quite bare unless for a 
minute lichen. 

As these clay cuts have been exposed for over three years to the severest rainfall 
of record on this continent and were found in better condition on the whole than an 
exposure in the United States for a single winter would have left them, it is evident 
that the absence of frost more than balances the tropic downpour, and for the mate¬ 
rial in question constructions can quite as safely be designed as in the United States. 
* * * r fhe na tural growth in the roadbed was unexpectedly slight, although in 
two or three cases the canebrakes had invaded the track. 

On the whole, taking into account the condition of the sand dumps at Greytown 
and of the clay cuts and fills on the line of the railroad, it is evident that the heavy 
rainfall is not necessarily as formidable an obstacle to outdoor construction as might 
be supposed. 

The geologist, Dr. Hayes, also states, concerning the resistance of 
the slopes to abrasion on the western division, that— 

The present channel of the Rio Grande is from 15 to 25 feet in depth and its sides 
are generally steep, often nearly or quite vertical. They serve to show the capacity 
of the material to stand at very steep slopes. It would also probably form fairly 
impervious embankments. 

There is no reason, therefore, for departing from the usual engi¬ 
neering practice, unless it be to make the slopes steeper and thus 
reduce the cube of excavation and the consequent cost of the work. 

SANITARY AND CLIMATIC. 

The impression that this position of the Isthmus is usually unhealthy 
is erroneous. On the contrary, the local conditions are such that with 
ordinary hygienic precautions the risks from disease are slight. 

The frequent rainfall on the east coast furnishes an ample suppty of 


INTEROCEANIC CANAL. 


15 


fresh soft water, condensed directly from the clouds; the porous, sandy 
soil absorbs it so rapidly as to prevent stagnation, while animal refuse 
is quickly removed by the scavenger birds and lish, continually on the 
alert for food. 

W ith their light, loose clothing, vegetable diet, and cleanl} T habits, 
the natives seldom suffer from fevers. Even our unacclimated Ameri¬ 
cans passing from a rigorous winter temperature to the mild region 
of the trade winds were, with few exceptions, exempt from febrile 
complaints, and among the large number of engineers sent out there 
was no mortality in the country. The constant motion of the wind, 
sweeping through the low divide, appears to remove the noxious 
exhalations which characterize other portions of the Isthmus. Yellow 
fever tinds no habitat at Greytown, and even when imported it does 
not become epidemic. Abstemious habits and careful police of camps 
will insure as good health among laborers as will be found in many 
localities in this country. The climate would affect the labor ques¬ 
tion, therefore, chiefly by the lassitude resulting from its enervating 
influence. 

Assistant Engineer Stuart says that— 

The atmospheric conditions are excellent, and for the seven months we were in 
the field we worked in all conditions of weather, losing but one entire day on 
account of a heavy downpour of twelve hours. 

• The narrow limits within which the temperature ranges are shown 
from a few selected observations at various stations during the year, 
as below. The Rio Viejo station is located on the western slope of the 
Cordilleras, east of the lake and at a higher altitude than the others. 
Hence its greater range of 30°. This uniformity of temperature is 
one of the important factors in the consideration of the permanency of 
important works as well as in the health of the inhabitants. 


Exhibit of extreme range of the observed temperature in Nicaragua. 


Location. 

Date. 

Maximum. 

Minimum. 

Date. 

Range. 

Rritoa.nrl Tola stations. 

1898. 
Dec. 22 

°F. 

’ 88 

° F. 

75 

1898. 
June 28 

o 

13 

T,as La.jas station. 

May 12 
Mar. 3 

91 

73 

Sept. 10 
Mar. 12 

18 

Rio Viejo station. 

97 

62 

35 

Rort San Carlos station. 

May 8 
Mar. 20 

91 

70 

Mar. 28 

21 

Sa ha 1 os sta.ti on. 

90 

65.2 

Dec. 25 

24.8 

San Carlos River.. 

May 7 
Oct. 1 

95 

66 

Feb. 7 

29 

Oehoa: station _ . 

95 

66.5 

Jan. 3 

28.5 

Deseario River sta.tion. 

May 25 
Sept. 29 

91 

65 

Jan. 3 

26 

Grevtown. 

96 

69 

Mar. 14 

27 






EARTHQUAKES AND VOLCANOES. 

From the most reliable data obtainable the Commission believes that 
the canal region is practically exempt from any seismic influences of 
sufficient force to cause destruction or danger to any part of the canal 
route or suspension of its traffic. Dr. C. W. Hayes has treated this 
question fully in his report. a He says that— 

Earthquakes due to the dislocations of strata (faults) are perhaps no more liable to 
occur in the vicinity of the Nicaragua Canal route than elsewhere, and hence they 
do not constitute a danger which is peculiar to this region more than to almost any 
other in which a ship canal might be constructed. 

a See Report of Dr. Hayes, Appendix II. 































16 


INTEROCEANIC CANAL. 


He then proceeds to discuss those due to volcanic agencies at some 
length, and concludes that those activities are on the wane and so 
remote from the route as not to constitute a menace. In quoting from 
Major Dutton, he adds: 

Briefly, then, the risk of serious injury by earthquakes to the constructions pro¬ 
posed for the Pacific section of the canal is so small that it ought to be neglected; 
* * * also that the risks to the Atlantic section are still smaller than those to the 
Pacific section. 

MATERIALS FOR STRUCTURAL PURPOSES. 

The cost and durability of the canal are also affected by the char¬ 
acter and distribution of such native material as ma}" be utilized for 
the purposes of construction. These consist chiefly of earth, rock, 
timber, and sand, all of which are abundant and free. Cement, iron, 
explosives, tools, plant, and some provisions and clothing will need to 
be imported, but will be exempt from duty. 

ALLUVIUM. a 

All unconsolidated material which has been transported and deposited by streams 
is classed as alluvium. * * * It varies considerably in composition, depending 
upon the source from which it was derived and the manner in which it was deposited. 
It varies all the way from coarse, clean-washed sand or gravel to the finest clay. 
It may for convenience be separated into three subclasses: (1) sand, (2) silt, a variable 
mixture of fine sand and clay, and (3) clay silt, composed chiefly of clay, with little 
or no sand. All three subclasses contain variable quantities of vegetable matter. 

The alluvium is everywhere of such character that it can be easily handled with 
dredges. Almost everywhere the silt and clay silt are sufficiently solid to stand at 
moderate slopes, the slope of one on one probably being sufficient. In some cases, 
as in the Florida lagoon, special precautions may be needed to preserve the slopes. 
The material becomes very hard when dry, and even when it is piled up so that, the 
water can drain off it becomes comparatively firm. This is shown in the vertical 
stream banks where drainage is possible, while the same material forms a soft mud 
in the swamps at some distance from the stream channels. The black sand when 
free from clay is of course quite pervious to water and would not be suitable for banks 
where the water level was permanently different on its two sides. This material, how¬ 
ever, will not be encountered beyond the site of the first lock on the proposed low- 
level line. It is probable that wherever the canal is more than half in excavation 
the silt will form banks sufficiently impervious to hold the required height of water 
without the addition of any other material. Where the head is greater than 15 feet 
it may be necessary to add a puddled core to the bank unless the latter is made of 
more than ordinary thickness. 

SAND. 

The black volcanic sand of the east coast and lower river section is 
not composed of the partly-decayed minerals derived from a deeply 
weathered rock, but is made up entirely of finely-comminuted frag¬ 
ments of fresh volcanic rock, evidently broken up and ejected by 
explosive volcanic eruptions. It would thus make a good, sharp, 
clean material for hydraulic mortar, concrete, or beton. Its specific 
gravity is 1.68, or 101 pounds per cubic foot, comparing very favor¬ 
ably with the best building sand in the United States. 

CLAY. 

Clay of excellent quality is abundant and well distributed. When 
mixed in suitable proportions with sand and gravel it makes an admir¬ 
able puddling material. 


a See Report of Dr. Hayes, Appendix II. 






INTEROCEANIC CANAL. 


17 


Quartz occurs in only a few of the rocks, so that much of the clay is remarkably 
free from grit, tough and compact. Although it is penetrated by numerous roots and 
burrowing insects, the absence of frost permits it to remain more compact than any 
surface clay in higher latitudes. Next to the silt it will form by far the largest part 
of the excavation. It will make perfectly impervious embankments if some means 
are taken to puddle it as it is deposited, but probably if simply dumped in the bank 
it would be pervious to water. a 

WOOD. 

N umerous large trees occur in the forests along the river and on the 
border of the lake which are denser and stronger than our American 
oaks and pines. The clearing of the canal route will also furnish a 
large number of cross-ties. Some of these native woods, according to 
Colonel Childs, will last above ground from forty to fifty years. The 
madera negra is one of the most valuable ties and is abundant. It 
may also be obtained for dimension timber up to 30-foot lengths and 
11 inches square. 

The nispera will cut in lengths of 50 feet and square 18 inches. It 
is .very common and durable, but heavy. Many other varieties exist, 
as the palo cortez, guachipilin, roble, cocobole, pine, cedar, niambaro, 
caoba or mahogany, paolo-de-arco, granadillo, guayacan, almendro, 
feniscaro, etc. The shipment of timber is one of the industries of the 
port of San Juan del Sur. As much of the native timber is valuable 
for export, and as no mills exist for its local manufacture, it may 
doubtless prove more expedient to import the piling and dimension 
material from the extensive forests of the Southern States and to use 
the local product mainly for fuel and ties. 

SHELTER. 

There is also ample material available without cost for the protection 
of men and materials from the rain and sun. The usual habitations of 
the natives consist of a carefully laid thatched roof, substantially 
built, reaching nearly to the ground, with walls of bamboo or adobe. 
These afford free circulation of air and are cool and dry. Their only 
cost is for the labor*of erection, which is slight. 

The fuel in general use is wood, which is cut and stacked under 
shelter on the banks of the river. A considerable quantity of cord 
wood can be secured from the clearing of the route and adjacent for¬ 
ests. In some localities water power may be made available. 

IRON AND STEEL. 

These metals will necessarily be imported, but the climatic condi¬ 
tions are such as to cause remarkably little deterioration. Templates 
of the rails which have been exposed to the rain and sun for about 
nine years do not exhibit any measurable loss in section of weight. 
The spikes also retain the sharp edges of the tool marks on their heads 
and shanks. Only where the salt water of the ocean reaches the iron 
rails and bolts on"the pier is there any considerable amount of scale 
visible. 

STONE. 

A large amount of material on the route of the canal, classified as 
rock and soft rock, will require excavation to create the channel. A 

a See Report of Dr. Hayes, Appendix II. 


S. Doc. 264, 59-1-2 







18 


INTEROCEANIC CANAL. 


portion of this is suitable for structural purposes. On the western 
division the rock is generally a calcareous nonfissile shale, interstrati- 
fied with beds of sandstone varying from a few inches to 2 or 3 feet 
in thickness. The shales constitute the greatest bulk of the rock to 
the eastward of Brito Head, where the sandstones of the northern 
headland are too thin for use as building stones but are suitable for 
concrete or riprap. 

About half a mile east of Brito, however, is found a group of heavy 
sandstone beds forming a spur extending into the Rio Grande Valley. 

These beds would probably yield a good quality of dimension stone; would be 
easily quarried in dimensional blocks up to 20 or more inches in thickness; would 
dress readily and be as durable as the average sandstone. 4 

North of the canal line at Buen Retiro is a large deposit of intruded 
andesite or trap, which makes a very desirable material for structural 
purposes. 

It is probable that all the material on the west side which has been classed as soft 
or disintegrated rock can be excavated with a steam shovel without blasting. The 
material stands in natural slopes of 60° or more (to the horizontal), and artifical 
slopes equally steep will probably be entirely safe. 4 

The rocks on the eastern division are chiefly of igneous origin, but 
from a few miles below Castillo to halfway between Machuca and 
Boca San Carlos they are largely sedimentary with a few small igne¬ 
ous dikes. 

No coarse conglomerates nor pure limestones have been discovered 
in this formation, although they may occur. 

The beds of massive sandstone exposed on Machuca Creek, being to a large extent 
free from joints, could probably be quarried for dimensional building stone, which 
would be easily worked and fairly durable. 4 


The principal varieties of the igneous rock found in this section are 
aug it e-andesite, olivine basalt , hypersthene basalt , and dacite. The 
first three are commonly known as trap rocks. They are generally 
compact and heavy. The dacite is lighter than the trap and some¬ 
what softer. (This was called conglomerate by the canal company.) 

The basalt (trap) extends from the Boca San Carlos eastward beyond 
the San Francisco hills, forming the Sarapiqui hills and others border¬ 
ing the lower portion of the San Juan River, as well as those in the 
vicinity of Silico Lake, and is suitable for dams, jetties, and concrete. 

The dacite is found at lower Ochoa and Tambor Grande, where it 
comes to the surface and continues to the Eastern Divide. It is there 
interbedded with the andesite tuffs and basalt. 

Associated with the above-named massive rocks is a group of frag¬ 
mental igneous rocks whose members vary from coarse conglomerate 
or breccia to beds of fine volcanic ash. The coarser varieties resemble 
in their physical properties the igneous rocks from which they are 
derived, while the fine ash is generally talcose and crumbles on exposure 
to the air. 

Deposits of hard rock also exist near the site of Lock No. 1 of the 
canal company’s line, to which the railroad has been built. 

> Several outcrops of rock reported to be suitable for jetty construc¬ 
tion exist on the coast at Point of Rocks and at Monkey Point, but no 
samples from these ledges have been secured. The quarries are readily 
accessible from the sea and furnish material for ballast to coasters. 


4 See report of Dr. Hayes, Appendix II. 





INTEROCEANIC CANAL. 


19 


CLASSIFICATION AND WEATHERING. 

The three classes of materials—alluvium, residual clay, and soft rock—should be 
considered as earth in making estimates for excavation. The soft rock, however, 
may require some blasting, particularly toward the bottom and where it contains 
very large bowlders. It will stand with much steeper slopes than the silt and clay 
and will be less liable to slip. Not being plastic, it will also support a heavier load, 
and hence may be relied upon for foundations where the weight of the structure is 
not excessive. For these reasons it seems desirable to make the distinction between 
clay and soft rock wherever possible. 11 

The weathering of rocks is brought about by two processes—rock 
disintegration and rock decay. The first varies directly and the second 
inversely with latitude when humidity is constant. The first process 
depends on changes of temperature and expansion of interstitial water 
by freezing, hence is inactive in the Tropics. The second process 
depends on high temperature and a rapidly decaying vegetation, hence 
is inactive in the Tropics. Special attention is directed to the fact that 
it is chiefly the first process of disintegration which is inimical to the 
permanence of structures, and hence that their relative durabilit} 7 will 
be greater in the Tropics than in higher latitudes. 

Such being in brief the pl^sical conditions of the route, it remains 
to determine the dimensions, which all things considered, will best 
subserve the interest of the world’s commerce in making this transit 
of the Isthmus. 

DIMENSIONS OF CANAL. 

To provide ample facilities for the safe and expeditious passage of 
vessels the trunk of the waterway has been considerably enlarged 
over that of any previous project. The dimensions adopted by the 
Commission as the basis of the estimates are as follows: 

The canal nowhere to be less than 30 feet in depth. The width 
varying with the local conditions as follows: From Grey town Harbor 
to Boca San Carlos the width to be 150 feet, Avith slopes in earth of 
1:1 and in alluvial silt of 1:2. In hard rock vertical sides up to 40 
feet from the bottom, then slopes of 5:1. In soft rock the slopes to 
be 2:1. 

In the river the width at bottom to be 300 feet, with slopes of 1:2, 
with enlargements at the bends, and at the eastern end of the lake the 
excavation to be 600 feet wide at the outer end, decreasing to 300 feet 
at the river, and having slopes of 1:5 to the depth of 6 feet and then 
1:3; for all routes from the Caribbean Sea to the lake, excepting the 
Menocal route, the same dimensions are used. The bottom width of 
the canal from the lake to the Pacific to be 150 feet, with slopes as on 
the east side, and the computations have been based upon a minimum 
lake elevation of 104 feet above mean sea level, Caribbean Sea, as a 
datum. The minimum radius is limited to 3,000 feet, with enlarge¬ 
ments of width in bends varying according to the degree of curvature. 

The locks are 80' x 30' x 665' between quoins, giving an available 
length of 620 feet, with variable lifts. 

Estimates were also made upon numerous modifications of the above 
dimensions. 

For convenient reference and comparison with the canal prism as 


a See Report of Dr. Hayes, Appendix II. 




20 


INTEROCEANIC CANAL. 


proposed by the Maritime Canal Company the areas of the several 
cross sections and the percentages of increase are stated herewith: 



Area of 
cross sec¬ 
tions in 
square feet. 

Per cent 
of in¬ 
crease. 

Between jetties, Grevtown. 

23,400 
14,700 
6,100 
5,400 
4,500 
9,900 
10,800 
( 7,272 

\ 13,272 

4,500 

5,850 


Entrance to harbor, Grevtown. 


Coastal section. 

10.3 

9.1 

50.0 

131.0 

84.0 

73.0 

216.0 

50.0 

8.0 less 

Canal proper. 

Through rock. 

In the river (in rock). 

In the river (in earth). 

In the lake. 

WEST SIDE. 

Western Divide. 

Across costal plain. 



Distances along the line of the canal route proposed by this Commission from the 7-fathom 
curve in the Pacific Ocean to the 7-fathom curve in the Caribbean Sea. 


Miles. 

1. Brito Harbor. 0.93 

2. Brito to Buen Retiro. 8.12 

3. Buen Retiro to west side of lake. 8. 71 

4. Lake Nicaragua. 71.34 

5. East side Lake Nicaragua to Boca San Carlos... 56. 96 

6. Boca San Carlos to Sarapiqui. 21. 59 

7. Sarapiqui to Grey town. 20.59 

8. Greytown Harbor... 1. 74 


Total. 189. 98 


REGULATION OF THE LAKE LEVEL. 

All plans for a canal by the Nicaragua route contemplate using the 
lake as the summit for the canal and as a feeder. The regulation of 
its level is therefore a matter of the greatest importance. 

It is known with reasonable certainty that the lake has varied in its 
elevation above sea level as much as 13 feet. It has probably been as 
low as 98 feet above mean sea level and as high as 111 feet above the same 
plane. These extremes have occurred at relatively remote intervals, 
but their occurrence must be admitted, and their recurrence in the 
absence of regulating works must be reasonably anticipated. It is also 
known, as a result of the observations of 1898, that notwithstanding the 
losses due to the outflow through the San Juan River and to evaporation, 
the lake has risen as much as 2 feet in six weeks. 

The higher the lake is held the less will be the excavation in the 
upper level, and as this is a heavy item in the cost of construction, the 
effort has always been to keep that level up as high as practicable 
without causing unnecessary damage to private property. On the 
other hand, a spillway of capacity sufficiently great to prevent the 
lake from rising is expensive. The problem, therefore, is how best to 
meet the varying conditions. A careful investigation has been made 
of the discharge of all streams of importance, measurements of rainfall 
observed at points widely distributed throughout the basin, and the 
rate of evaporation from the lake surface determined. 

The area of Lake Nicaragua, in round numbers, is 3,000 square miles, 
nearly 2,000,000 acres. The drainage area, including both lakes, is 
































INTEROCEANIC CANAL. 


21 


about 12,900 square miles. During the dry season of 1898 measure¬ 
ments were taken to determine the total inflow into Lake Nicaragua, 
which was found to be only about 1,700 cubic feet per second, showing 
that in the dry season the inflow into the lake is very small, scarcely 
worth considering. Nearly all the streams showed evidences of being 
stagnant several months, yet the }^ear 1898 was one of more than 
average rainfall. 

RAINFALL. 


Observations to determine rainfall have been kept at Rivas for the 
last nineteen years. During the year 1898 observations were taken at 
several scattered stations in the drainage basin to determine the rainfall 
of the lake region. These records are given in the accompanying 
appendices. 

Comparing the records at Rivas for the year 1898 with those for the 
other points it will be noted that the rainfall at Rivas was greater than 
the average for other parts of the basin, that at Rivas being 108 inches 
and the average in the basin 78 inches, a difference of about 28 per 
cent in favor of Rivas. This might at first appear anomalous, but it 
may be accounted for by the peculiar topographical features of the 
country in connection with the prevailing winds. It will therefore be 
assumed that, in order to obtain the rainfall in the basin for other 
years than that of 189,8, the Rivas record will have to be reduced by 
28 per cent. The number of observation stations in the basin are not 
great, but they offer a basis for estimating rainfall in those years for 
which there is no other record than that of Rivas. 

There are two distinctly marked seasons in the drainage area of the 
lake—the wet and the dry. The latter begins about December 15 and 
lasts until about May 15, a period of five months. The wet season 
then begins and lasts until December 15 following. This period has a 
duration of about seven months. It is probable, however, that the 
length of the wet and dry seasons may vary in some years, but it is 
well understood among the people in that region that those are the 
dates from which they are reckoned, and the observations for the year 
1898 confirm this. 


EVAPORATION. 


The amount of evaporation as determined for the year 1898 was 52 
inches. That year was an abnormally wet one and it is therefore prob¬ 
able that the evaporation was somewhat below the average. Mr. Davis 
estimates a normal annual aggregate at about 60 inches, or five feet. 
The amount of evaporation in the lake itself is greater during the dry 
and less in the wet period. It has been taken at 1 inches per month 
during the wet period, and 6 inches during the dry, which corresponds 
closely with the observations for 1898. 

These results have been checked b}^ the Commission’s study of the 
exhibits, as follows: 

From Plate XVIII, Appendix III, it appears that during the year 
of 1898, throughout which careful observations were made, the lake 
fell about 3.09 feet between January 6 and May 15, a period of 131 
days or 4.5 months, while in the following season of rainfall it rose 
4.72 feet by December 5, when it again began falling. The net grain 
in storage during this entire year from January 5, 1898, to January 
5, 1899, was 15.6 inches. 


22 


INTEROCEANIC CANAL. 


It will be observed that during that portion of the season beginning 
February 1 and ending May 15 the lake surface declined uniformly 
(the slight fluctuations being due to wind and not to rainfall), and that 
in this time the total rainfall did not exceed 2f inches over the lake 
surface. The run ofl from the parched ground at this season is prac¬ 
tically zero. Hence the only gain was the direct rainfall wdiile the 
losses were those due to evaporation and outflow, which latter quantity 
was measured by continuous observations at the Sabalos station on the 
San Juan River, the only outlet. 

The outflow between February 1 and May 15 is given as 2,817,748 
acre-feet, equivalent to a vertical depth over the lake area (2,000,000 
acres) of 1.408 feet. If this be deducted from the loss in storage and 
rainfall, which is 2.840 feet, it leaves 1.432 feet loss due to evapora¬ 
tion in one hundred and four days, or a diurnal rate of 0.165 inch (one- 
sixth inch), or 5 inches per month, or a rate of 5 feet per annum for a 
dry year. This being deduced during the dry season would doubtless 
represent the maximum for the year. 

RUN-OFF. 


The run-off or inflow to the lake from rainfall on its drainage basin, 
exclusive of the lake proper, for the year 1898 has been found to be 
about 30 per cent of the rainfall. This is computed as follows: The 
average rainfall at six stations in the basin of Lake Nicaragua for 1898 
was 78.29 inches. During that year the lake rose 18 inches. The out¬ 
flow, if held, would have raised the lake 84 inches. Evaporation as 
determined was 52 inches, so that if there had been no outflow nor 
evaporation the lake would have risen 154 inches. Of this, 78.29 was 
by direct fall on the lake, leaving 75.7 inches as the rise due to the 
fall on the land, or the run-off. The area of the lake is 3,000 square 
miles; the area of the tributary basin is 9,900 square miles. The lat¬ 
ter is therefore 3.3 times that of the former. Dividing the inflow 
into the lake, 75.7 inches, by 3.3, the ratio of the lake surface to the 
exterior drainage, we have 22.94 inches as the rise due to run-off. 
This is 29.3 per cent of the rainfall. 


LOCKAGE. 

When the canal is built the lake will be drawn upon for water for 
lockage and for power. There will also be some leakage, the amount 
depending largely on the kind of dams and waste ways used. The 
estimate for leakage is necessarily arbitrary, but a computation based 
on large traffic through the canal gives 3 inches as the estimate for 
annual requirements for lockage, leakage, and power. 

REGULATION. 

The surface of the lake is acted upon by several opposing forces. 
They must be so regulated that its fluctuations can be controlled within 
proper limits. Evaporation, outflow, and use of the canal will lower 
the lake’s level. Rainfall and inflow will raise it. Water must there¬ 
fore be stored for evaporation and use, and the excess of rainfall and 
inflow be discharged. For purposes of storage against evaporation 
years of minimum rainfall must be considered, and for determining 
spillway capacity years of maximum rainfall. 

The data for an absolute determination of these problems would 


INTEROCEANIC CANAL. 


23 


necessitate a series of observations extending over many years. But 
with the records for 1898, in connection with the rainfall records of 
Rivas for the past nineteen years, conclusions may be reached which, 
while they ma} r not be absolutely correct, will be sufficiently close for 
all practical purposes. 

The year of minimum rainfall, as determined by the Rivas record, 
is 1890. During that year 31.81 inches of rain fell. If this be reduced 
. by 28 per cent, the difference between Rivas and the average of other 
parts of the basin, we have 22.9 inches as the average for the basin in 
an extreme dry year. It is well known that variations in annual rain¬ 
fall are greater at single stations than over an extended area. It is 
therefore probable that this estimate is too low for a very dry } r ear. 
Twenty-eight inches have therefore been assumed as the minimum 
annual rainfall in the basin. 

The estimated run-off for 1898 was 29.3 per cent of the rainfall, and 
as the run-off will diminish with the diminution of rainfall, 25 per cent 
of the rainfall has been taken as the average for a dry year. We then 
have 28 inches falling directly on the lake and 28 inches on the drain¬ 
age area tributary thereto. The latter being about 9,900 square miles, 
enough water would fall on the land to raise the lake 23.1 inches. This 
added to that falling direct would raise the lake 51.1 inches if all sources 


of loss were cut off. But the loss from evaporation would be about 
60 inches, and 3 inches would be lost by lockage, leakage, and use—a 
total of 63 inches, or 5 feet and 3 inches. There would, then, be a 
deficit of 11.9 inches at the end of the year. If the year ends with the 
end of the wet period, the succeeding dry period will be begun with this 
deficit. For this period, lasting about five months, during which the 
lake would receive practically no rain and evaporation would be at the 
maximum, the loss to the lake would be 30 inches for evaporation and li 
inches for lockage, leakage, etc.; total loss, 31i inches, which, added 
to the deficit of 11.9 inches, gives 13.1 inches as the deficit at the 
beginning of the wet season, when the lake would probably fill up 
again. Temporary storage of about 1 feet in the lake is therefore 
needed to provide for evaporation and use in a time covering two dry 
periods and one wet one. In other words, if the lake had been at 108 
at the beginning of the first dry period it would have fallen to 101 at 
the end of the succeeding dry period. 

Substantially the same result is reached by Mr. Wheeler in another 
way (see his report). 

In a year of maximum rainfall and minimum evaporation the condi¬ 
tions are reversed. The problem will be to get rid of surplus water 
and prevent the lake from rising to a high level. 

The year of maximum rainfall, according to the Rivas record, was 
in 1897, when 123 inches fell. Reducing this by the 28 per cent ratio 
we have a rainfall in the basin of 88.6 inches for the maximum year. 
As before stated, the variation in annual rainfall over a large area is 
not as great as it is at one station. It is therefore probable that for 
the entire basin this estimated rainfall is too great. Suppose it be 


taken at 84 inches, or 7 feet, there results: 


Rainfall direct on the lake. 84 inches. 

Run off, 30 per cent, about. 84 inches. 


Total inflow. 168 inches. 

Deduct for evaporation and use. 63 inches. 


105 inches = 8' 9" 








24 


INTEROCEANIC CANAL. 


This represents what must be taken care of by storage and discharge. 

This rainfall will not be extended uniformly over a year, but most 
of it will fall within the wet season of seven months. A mean dis¬ 
charge of about 40,000 cubic feet per second would discharge it all in 
this time; or if 4 feet be stored in the lake, a mean discharge of 
22,000 cubic feet per second would take care of it. Inasmuch as it is 
impossible to know in advance whether the rainfall of a season is to 
be heavy or light it will not be safe to begin discharging at the full 
capacity of the outlet until enough water has been stored for possible 
deficiencies. Consequently, instead of having seven months’ time in 
which to discharge the surplus, a large part of it might have to be 
discharged in a less time, and a spillway of greater capacity would be 
needed. With a spillway capacity of 50,000 cubic feet per second the 
entire surplus could be handled in about ninety-two days. 

The following method is used by Mr. E. S. Wheeler for determin- 



rainfall: 


Between June 18 and October 29, 1898, a period of one hundred and thirty-two 
days, the rainfall at Rivas was 76.36 inches; the lake rose 48 inches; the outflow 
lowered it 32.76 inches and the evaporation of the lake surface lowered it 16.38 
inches. Therefore, if there had been no evaporation on the lake nor outflow from 
it, it would have risen 97.64 inches. 

Between May 17 and October 27, 1897, a period of one hundred and sixty-four 
days, the rainfall at Rivas was 112.42 inches. This was the period of greatest rain¬ 
fall shown in the Rivas records since 1879. The amount of fluctuation in the surface 
of Lake Nicaragua caused by this rainfall was not observed; an attempt will be made 
to determine it by comparison with the wet portion of 1898, when both fluctuations 
and rainfall were carefully measured. The problem may then be briefly stated as 
follows: If a rainfall of 76.36 inches in one hundred and thirty-two days would cause 
a rise in the lake surface of 97.64 inches, what rise would be caused by a rainfall of 
112.42 inches in one hundred and sixty-four days? The ratio between rainfall and 
change in lake level, as given in the preceding table, can not be used for this prob¬ 
lem, because in this case only portions of a season are considered. At the beginning 
of these periods the streams and marshes were drained and empty; at the end they 
were overflowing and the entire run-off due to the rainfall had not yet occurred. 
Therefore this problem must be solved as a special case. If the rise was exactly 
proportional to the rainfall it would be 143.7 inches, provided there was no evap¬ 
oration on the lake or outflow from it. It is, however, probable that in this case, as 
in the preceding one, the greater daily rate of rainfall in 1897 would cause the lake 
to rise slightly more than the proportional amount. An examination shows that 
the daily rate of rainfall in 1897 was 18 per cent greater than in 1898. Using the 
ratio as before, the rise in the lake would be 22 per cent greater. Applying this 
per cent, the computed rise in the lake for 1897 would be increased from 143.7 inches 
to 148.58 inches. This, then, is the estimated amount of fluctuation that would have 
occurred during the period of greatest rainfall of the last twenty years if there had 
been no evaporation on the lake or outflow from it. 

The question as to what amount of fluctuation in the lake will be necessary to take 
care of this rainfall will next be considered. The estimated rise of 148.58 inches 
must be provided for by evaporation, outflow, and temporary storage in the lake. 

Assuming the ratio of evaporation from the lake surface to be the same as in 1898, 
it would for the one hundred and sixty-four days amount to 20.97 inches. Subtract¬ 
ing this from 148.58 inches leaves 127.61 inches that must be provided for by the 
outflow and temporary storage. 

The lake has an area of 3,000 square miles; a rise in its surface 127.61 inches 
would be equivalent to 889,408,618,000 cubic feet. If this should run out of the lake 
in one hundred and sixty-four days the mean discharge would be 62,769 cubic feet 
per second and there would be no change in the elevation of the lake surface. If 
the lake should be permitted to rise 1 foot then the mean discharge would be 
reduced to 56,866, and each additional foot that the lake is allowed to rise will 
reduce the mean rate of discharge by an equal amount. The following table shows 
the required rate of discharge for each foot of fluctuation: 

0 feet require 62,800 cubic feet of discharge. 

1 foot requires 56,900 cubic feet of discharge. 


INTEROCEANIC CANAL. 


25 


2 feet require 51,000 cubic feet of discharge. 

3 feet require 45,100 cubic feet of discharge. 

4 feet require 39,200 cubic feet of discharge. 

5 feet require 33,300 cubic feet of discharge. 

I* appears from this table that if a waste-way having a capacity of 33,000 cubic 
feet per second be provided, the fluctuation in the lake could be limited to 5 feet 
for rainfall—as great as any that has occurred in the last twenty years. 

Since the canal itself will incidentally provide waste-ways exceeding this in 
capacity, it appears that not more than 5 feet of rise will be caused by the largest 
rainfall. Therefore no addition need be made to the 6 feet already provided for 
dry periods. 

The Commission has therefore concluded that in any plan of a canal 
by the Nicaragua route a spillway of 50,000 cubic feet per second 
capacity should be provided, and that the lake may vary in its level 
from elevation 104, the minimum, to 110, the maximum. 

The endeavor would be to approach the dry season with the water 
level of the lake at about 108, and during that dry season to draw it 
down to 106, if it did not go to that level from natural causes. At the 
beginning of the wet season the lake would be allowed to rise, but 
when it reached 108 the spillwa}^ would be opened, gradually at first, 
and at its full capacity if necessary. In this way there would be a 
margin of 1 feet for the lake to fall in dry seasons and the same amount 
for it to rise during wet seasons. This is believed to be ample. 

The possibility of securing complete control is manifest by inspec¬ 
tion of Plate XIX«, a which shows that had all the water entering the 
lake been impounded, the surface during the first twenty days of Jan¬ 
uary, 1898, would have risen 3 inches, or, since there was no rainfall, 
that the run-off and seepage from the previous season were still feed¬ 
ing it. 

From this period it would then have declined quite uniformly from 
loss by evaporation until the end of the dry season, May 15, when it 
would have stood at an elevation of 101.07 above datum, after which 
it bore a nearly constant relation to the accumulated rainfall and would 
have reached its highest level of 113.69 on January 20, 1899, a gain of 
9.6 feet in about eight months had all the water been held. If, on the 
contrary, it had been desired to prevent any further rise at any par¬ 
ticular stage, even the lowest, it might have been done by a spillway 
having a capacity of discharge indicated by the red line of the chart, 
which represents an increment at the rate of 15,910 cubic feet per 
second. With this spillway capacit} r for this year the lake could have 
been held at any desired stage, or, by a reduction of the discharge, it 
could have been allowed to fluctuate within any reasonable limits. 

A spillway of 50,000 cubic feet capacity divided between the eastern 
and western outlets will afford ample facilities for the regulation and 
control of the lake and its drainage. 

The relation of such a spillway capacity to the observed fluctuations 
during 1898 may be exhibited graphically by assuming this quantity of 
water to be poured into the lake basin and drawing a curve represent¬ 
ing the rise due to this inflow, all the water being stored. (See Plate 
XIX, Appendix III.) 

By taking the difference between the curve representing the lake 
fluctuation and the curve representing 45,910 second-feet at any date, 
as, for example, on July 14, and plotting this difference, the result 
will represent the fluctuation of the lake under the physical conditions 


“See Plate XIX« in Atlas. 




26 


INTEROCEANIC CANAL. 


as they existed between July 14 and the end of the record. Had the 
sluices remained closed between January 1 and July 14 the lake would 
have risen to 107, and if then thrown fully open the lake would have 
risen only 1 inch higher during the entire season. Had they been 
entirely closed again on October 28, the lake would have gained 2 feet 
more in storage preparatory to the next dry season, which it would 
have entered at 108.68. By closing earlier more water could have 
been stored. This matter could readily be regulated by the judgment 
of the manager, who would doubtless have closed the valves through¬ 
out the dry season and thus have stored the entire outflow during that 
time. 


* LOCATION OF SPILLWAYS. 

An important matter in connection with the regulation of the lake 
level is the location of the regulating works or spillway. It is seen 
that the lake may at times have to discharge as much as 50,000 cubic 
feet per second. An ideal arrangement would be to have the spillway 
entirely independent and separated from the canal proper or canalized 
river. A careful search has been made for such location on the west 
side between the lake and the Pacific, but no suitable place could be 
found that did not involve an expense almost as great as the construc¬ 
tion of the western division of the canal itself. It has therefore been 
suggested that this surplus water might be discharged through the 
canal itself as far as Buen Retiro, and there turned into the valley of 
the Rio Grande, which it would be forced to follow on its way to the 
sea. This plan is objectionable for several reasons. 

It will necessitate a widening of the canal proper from the lake to 
Buen Retiro, a distance of about 9 miles, the most of which will be 
excavation in rock. This part is the Divide cut of the western divi¬ 
sion. Even if this cut be made reasonably wide, the current through 
it will be swift. Of course the greater the width the less the current, 
but it may be questioned whether a current of 5 feet a second in a 
canal 200 feet wide would be entirely satisfactory to navigation. 
Moreover, 200 feet width will only discharge about 35,000 cubic feet 
per second with a 5-foot current, and there may be times when the 
discharge ought to run as high as 50,000 cubic feet per second. 
To carry this amount of water with a 5-foot current would require a 
width of about 300 feet. 

A further objection would be the difficulty of properly controlling 
these discharged waters after they had left the canal. The discharge 
of 35,000 to 50,000 cubic feet of water per second into the valley of 
the Rio Grande means the creation of a torrential river 10 times the 
magnitude of the existing river in its highest floods. This might not 
be an insuperable objection if the valley of the river were rock or 
some material not easily eroded. The soil of this valley is for the 
most part light, sandy and easily put in motion by swift-running 
water. The distance from Buen Retiro to the Pacific is about 8 
miles, and the river in that distance would have a fall of about 80 feet 
from the foot of the spillway. Moreover, the canal itself will be 
located in this valley, and at the gorge the width is reduced to 2,000 
feet. A stream like the one thus created might endanger the canal 
itself. The difficulties of controlling it would be great, and a large 
amount of the material would be scoured and carried to the ocean, 


INTEROCEANIC CANAL. 


27 


perhaps to the great detriment of the entrance to the canal. It is 
possible that from 10,000 to 15,000 cubic feet of water per second 
might be discharged through the canal on the west side and into the 
Rio Grande river if widened and straightened without damage, but 
the discharge of two or three times that amount is believed to be 
impracticable except at unwarranted expense. 

Nor does there appear to be any absolute necessity for discharging 
all the surplus water of the lake on the west side. The San Juan 
River is to-day, and has been, its natural and only avenue of discharge. 
According to the estimates of the geologist and the hydrographer, its 
discharge in high stages has at times been as much as 50,000 cubic feet 
per second. The evidence appears to be conclusive that even this 
great discharge does not erode its banks to such a degree as to carry 
much sediment. The Agua Muerta below the Machuca Rapids indi¬ 
cates that no great amount of sediment is carried in the upper San 
Juan, and this notwithstanding the fact that the currents have been 
greater than they would be under the new condition of affairs created 
by the canalization of the river. The fact that the small tributaries 
that drain into the San Juan may at times discharge as much as 50,000 
cubic feet per second between the lake and the San Carlos River is 
objectionable, but such discharges come at rare intervals and last but 
a short time. Even if the regulating works could not take care of it, 
the only effect would be to raise the water in the river and stop the 
discharge from the lake for a short period, or possibly turn the cur¬ 
rent toward the lake. If, then, the San Juan River, discharging 
sometimes as much as 50,000 cubic feet per second in addition to that 
of its own drainage basin as it exists to-day, with a fall from the lake 
to the foot of Machuca Rapids of 18 feet, does not seriously erode its 
banks, it does not seem reasonable to expect more erosion when that 
fall is reduced and the discharge area of the river increased. 

The Commission has therefore concluded that the discharge from 
the lake through the canal and down the Rio Grande River on the west 
side should not exceed about 15,000 cubic feet per second, and that 
the remainder should be discharged through the San Juan River. The 
principal regulating works are therefore designed to be located at the 
site of the dam near Boca San Carlos, capable of a maximum discharge 
of 85,000 cubic feet per second, while the works on the west side 
should have a capacity of 20,000 cubic feet. 

PROJECTS AND ROUTES. 


The region within which a canal can be constructed is comprised 
within comparatively narrow limits. By the term “ Nicaragua Route" 
is understood a canal route which uses Lake Nicaragua as a part of its 
system. For convenience this may be divided into three divisions: 

" First. The division between the Pacific and the lake, called the western 
division; 

Second. The lake itself; 

Third. The division between the lake and the Caribbean Sea, called 
the eastern division. 


WESTERN DIVISION. 


Colonel Childs, an eminent civil engineer, in 1850-51, surveyed and 
located a route for a canal over this western division. His route, start- 


28 


INTEKOCEANIC CANAL. 


ing from the Pacific Ocean and going eastward from Brito at the 
month of the Rio Grande, followed the valley of this river to a point 
about 11 miles from the lake, thence across the Divide to the valley of 
the Lajas, which it followed to the lake. There was no harbor at Brito, 
and he proposed to form one by the construction of jetties and by 
excavating the alluvium of which the coastal plain is composed. A 
detailed description of the project is given in the report of the board 
of 1895. 

In 1873 a survey was made by Commander Lull, of the United States 
Navy. He proposed to construct a harbor at Brito and to follow the 
route suggested by Colonel Childs up the valley of the Rio Grande, 
but to cross the Divide farther to the north and to follow the valle}^ 
of the Medio to the lake. This line was somewhat shorter than the 
other, but involved heavier cutting in the Divide. A full description 
of this route is given in Commander Lull's report. 

Mr. Menocal, the chief engineer of the Maritime Canal Company, 
after further surveys, proposed to abandon the Medio route on account 
of the heavy cutting in the Divide, and adopted practically the route 
suggested by Colonel Childs. His first project was for a canal in 
excavation along the north side of the valley of the Rio Grande. 
Subsequently he suggested a modification of this project, which was 
adopted by the Maritime Canal Company, of building a dam at La 
Flor and creating an artificial basin 6.25 square miles in area, reach¬ 
ing from near the westerly side of the Divide to within 4 miles of the 
Pacific Ocean. At the proposed site of the dam the valley of the Rio 
Grande narrows to about 2,000 feet, and the surface indications of the 
adjacent hills seemed to promise good foundations for a dam. The 
construction of this dam would practically extend the lake level west¬ 
ward to within 4 miles of the Pacific Ocean. From the basin thus 

created the Pacific Ocean was reached bv a canal with three locks. 

_ 

The board of 1895 suggested still another project for a canal across 
this western division, which did not differ in location materially from 
that at first proposed by Colonel Childs, but followed the left bank of 
the Rio Grande instead of the right. These several routes are shown on 
the map accompanying this report, and a further description of them 
seems unnecessary, as full descriptions are to be found in the various 
reports and Congressional documents published by the United States 
Government from time to time. 

The relative advantages and disadvantages of these several routes 
will now be considered, but solely on a physical basis without reference 
to relative cost. 

The Menocal project of creating a basin in the valley of the Rio 
Grande by the construction of a dam at La Flor has the advantage of 
bringing the lake level close to the Pacific Ocean. The deep part of 
such a basin could be more rapidly and conveniently navigated than a 
canal in excavation. Moreover, the fiood discharges of the Tola and 
Rio Grande could be admitted into the basin without materially affect¬ 
ing the surface level, and it avoided all necessity for diverting the 
waters of these streams from the canal eastward of the dam. 

The disadvantages of this plan are, first, the La Flor Dam itself. 
Its crest would have to be about 120 feet above sea level, allowing 10 
feet for freeboard, while the solid rock is found at about 45 feet below 
sea level. The total height of the dam in the deepest part would, 
therefore, be not less than 165 feet. 


1NTER0CEANIC CANAL. 


29 


Second. If a high dam he built at La Flor to hold the level of the 
basin at 110 feet above sea level, all the locks will have to be placed on 
the west side of the Rio Grande. This is a disadvantage, because the 
area suitable is limited. 

The locks will necessarily be of high lift and located on the slope of 
the hills close to each other, where there is little room for additional 
locks should the} T become necessary by future developments in the 
commerce through the canal. Moreover, a part of the canal itself will 
necessarily be built with heavy embankments or retaining walls on the 
slope of these hills, and the iower Rio Grande will either have to be 
crossed, taken into the canal, or discharged to the eastward of the pro¬ 
posed harbor. 

Third. The creation of this basin would submerge many acres of 
land, not at present of great value, but which would become valuable 
should a canal be built. 

A canal in excavation, whether it follows the right or left bank of 
the Rio Grande, avoids the construction of the La Flor Dam, presents 
no special engineering difficulties, enables good sites for locks to be 
selected, and preserves for cultivation the fertile land bordering imme¬ 
diately on its banks. Of the two routes in excavation the one on the 
east side allows the river to discharge through its natural mouth on 
the west side of the proposed harbor. It is somewhat shorter than 
the other, but the most important advantage is that it enables the har¬ 
bor at Brito to be constructed on the east side of the Rio Grande, which is 
considered advisable, since it is contemplated to discharge a part of the 
water of the lake on the west side for regulation of lake level. 

The Menocal project could, however, be varied by providing a lock 
and dam at or near Buen Retiro and dropping down to a lower level. 
The basin would in this case be diminished in size, and the dam would 
be lowered in height by the number of feet lift in the lock. Less land 
would be submerged, but the basin would not be as deep nor as long. 
On the other hand, fewer difficulties would be encountered in con¬ 
structing the locks from the La Flor Dam to the Pacific, and the canal 
could be carried down to the sea on either side of the river with less 
difficulty. 

The Commission is of the opinion, in view of all the circumstances, 
that the best location is on the left bank or east side of the Rio Grande. 


LAKE DIVISION. 

The lake division will be the same for any project. 

EASTERN DIVISION. 

The projects that have been proposed and considered for the eastern 
division admit of more variants than those on the western division, but 
all projects for the eastern division look to canalizing the San Juan 
River by means of locks and dams from the lake to the vicinity of the 
mouth of the San Carlos River. 

Three projects with their variants are all that need be considered on 
the eastern side. 

The first is that for canalizing the San Juan River from its source 
at the lake to the sea. So far as the canalization of the river from the 
lake to Boca San Carlos is concerned, no doubt exists as to its practi- 


30 


INTEROCEANIC CANAL. 


cability. But for that portion of the river from thence to its mouth 
it is not deemed practicable, because of the difficulties of securing good 
foundations for dams, the torrential discharge of the San Carlos and 
Sarapiqui rivers and the great quantities of sand carried by them and 
deposited along the river channel of the Lower San Juan. 

A second project is that suggested by Mr. Menocal, which had for 
its object the extension of the lake level through the “Divide cut'* 
to within 12 miles of Grey town. It is similar to that suggested by 
him for the west side. It looked to the construction of a high dam at 
Ochoa a short distance below the mouth of the San Carlos River, by 
means of which the waters of the San Juan were to be raised to the 
level of the lake. From the south end of this dam embankments were 
to be built in the saddles of the San Carlos ridge, to connect with the 
hills in Costa Rica, thus cutting off the escape of the raised waters of 
the San Juan on that side. In this embankment line sluices were to 
be built to discharge the surplus waters of the lake which find their 
way down to the San Juan River, as well as the Hoods of the San Carlos 
itself. 

From the north end of the Ochoa Dam similar embankments were to 
be built across the saddles in the hills on this side, until connection 
was made with the high ridge known as the “Divide.” This was 
known as the San Francisco embankment line, and it crossed the rivers 
San Francisco, Danta, and Chanchos. The number of dams, large 
and small, was 67, those across the rivers named being the largest. 
This embankment line had a length of about 15^ miles from the north 
end of the Ochoa Dam to the Divide, of which 6 miles were artificial. 
Sluices were to be built at convenient places along this embankment 
to discharge the surplus waters of the drainage area to the northward. 

B}^ means of the Ochoa Dam and the San Francisco and San Carlos 
embankments a large pool or basin of irregular shape was to be created 
and the surface of the water maintained at or near the level of that in 
the lake itself. The excavation in the upper river and in the pool was 
thus reduced to a minimum. 

From a point near the eastern end of the Ochoa Dam the canal was 
carried in excavation to the valley of the Danta, or Florida Lagoon, 
and from thence in pools and cuts to the valley of the Limpio, which it 
followed to the Divide cut. This cut is about 3 miles long and has 
an average depth of 134.4 feet, the maximum depth being about 350 
feet. After crossing the Divide the canal descends, by means of three 
locks of high lift, into the valley of the Deseado, which it follows to 
the coastal plain, after reaching which it continues in a nearly direct 
line to Grey town. 

A third project is to construct a dam in the San Juan River just 
above the mouth of the San Carlos, giving slack-water navigation 
from the lake to the dam, and thence by a canal in excavation along' 
the left bank of the San Juan or near it to the junction of the San 
Juan with the San Juanillo, and from thence across the coastal plain 
to Grey town. 

Each of the two latter projects admits of variants. The Menocal 
project can be varied by locating the dam across the San Juan above 
the mouth of the San Carlos River, starting with excavation to the 
eastward of that dam and thence following a route substantially as 
projected by Mr. Menocal himself. Or a lock may be used in con¬ 
nection with this dam and the height of the embankments be corre- 


INTEROCEANIC CANAL. 


31 


spondingly reduced. This would increase the depth of the Divide cut 
by the same amount. The practicability of a dam only a short dis¬ 
tance above the mouth of the San Carlos River has heretofore been 
doubted, but the surveys show that such a dam is not only practicable 
but will be easier of construction than one at Ochoa. 

Another variant would be to build a dam near the Lower Machuca 
Rapids and lock down 24 to 30 feet, then follow the rest of the route 
practically as laid down by Mr. Menocal. the object of the latter 
variant being to avoid the construction of a high dam at Ochoa and to 
reduce the height of the San Francisco and San Carlos embankment 
lines. This would increase the depth of the Divide cut. 

Another variant would be to construct a dam at Tambor Grande and 
an embankment on the south side connecting with the hills in Costa 
Rica. This would take the place of the Ochoa Dam and eliminate the 
San Francisco and San Carlos embankments. This is regarded as 
impracticable. 

Other variants, such as increasing the number of locks or varying 
their location, suggest themselves. 

The third project can be varied by constructing one or more dams 
with locks in the upper river, thus reducing the height of the dam at 
San Carlos. Or after reaching the junction of the San Juan with the 
San Juanillo any one of several routes may be taken to the sea. 

Mr. MenocaPs project has an advantage in that it is 2 miles shorter 
than the other project following the bank of the river. a 

Its disadvantages are, first, the engineering difficulties encountered 
in building the Ochoa Dam. This dam being located but a short dis¬ 
tance below the mouth of the San Carlos River, its construction would 
be attended with no little risk. 

Second, the San Francisco embankment line is another troublesome 
engineering construction. This embankment follows an irregular line 
from Ochoa to the Divide. No less than 67 dams will be required, 
some of them insignificant in size, but four of them of great length 
and of more than ordinary difficulty to build and maintain, because of 
their great height and the pressure of water to which they would be 
subjected, as well as to the fact that the soil on which they would have 
to be founded is overlain for a great depth with soft ooze. 

A third disadvantage is the Divide cut itself. This, as before stated, 
is over 3 miles long. In addition it is curved, the curvature being in 
places the maximum that should be allowed in a canal of this magni¬ 
tude. This would render navigation difficult. Its great depth would 
also be a constant menace, for while it is believed that the rock for 
the most part would stand, there is some likely to cause trouble. 
A large portion of it, dacite, a rock that weathers rapidly, is of light 
specific gravity and not to be trusted in a deep cut like that through 
the Divide. Again, on account of its depth and length it would nec¬ 
essarily be made of the minimum width practicable for navigation; 
consequently if the canal were working to its full capacity, there would 
inevitably be some delay to vessels passing through it, since two large 
ships could not pass each other. Vessels would therefore accumulate 
at either end, to be passed at stated interrals in fleets. 

The variant providing for the construction of a lock and dam at 
Machuca, locking down, say, 24 feet, would reduce the height of the 

a Comparison of distances between the lake and Greytown Harbor. 









32 


INTEROCEANIC CANAL. 


San Francisco embankments and the Ochoa Dam; but the excavation 
in the San Juan River and eastward to the eastern end of the Divide 
cut would be increased hy this extra depth. There would still be the 
Ochoa Dam. though of less height, to be constructed in contention with 
the floods of the combined San Juan and San Carlos rivers. If the 
dam be built above the mouth of the San Carlos River instead of below 
it at Ochoa, there would vet remain the objectionable San Francisco 
embankments and the Divide cut. 

The project which looks to the construction of a dam above the mouth 
of the San Carlos River, and follows close to the north bank of the 
San Juan River as far as the junction of the San Juan and San Jua- 
nillo, has the disadvantage of an increase in length of about 2 miles, a 
but on the other hand it is believed the difficulties of construction will 
be lessened because of the reduction in the height of the embankments 
and b} r avoiding the Divide cut. 

There are, nevertheless, several hills of considerable height to be 
cut through on this route. The Tamborcito hill will require a maxi¬ 
mum depth of 230 feet of cutting in rock, but it is less than a half 
mile in length, and the material will be required on the work, while 
an attempt to circumvent the hills may involve an embankment 
founded upon a depth of 80 feet or more of black sand in the bed of 
the river. From this point to Lock No. 1 most of the canal trunk will 
be inclosed between embankments built of the silt from the excava¬ 
tions. In short distances they may exceed 30 feet in height, with a 
a pressure of 20 feet of water. 

A variant on this project will be in the construction of two dams in 
the river above the one near the mouth of the San Carlos. But it has 
no advantage over the other except that it enables the lower dam to be 
reduced in height. This is not considered of great importance, for 
while the construction would be easier, the main difficulty would be 
in the foundations, and they would not be materially different. It has 
several serious disadvantages, however, in obstructing the passage of 
large volumes of water at narrow sections of the river and in confining 
the navigation below the upper dam to a narrow channel excavated in 
large part through rock. 

Numerous other adjustments in detail may be made, both in the 
alignment and grade, but they are not of sufficient importance to 
warrant consideration prior to final location. 

GREYTOWN HARBOR. 

A suitable harbor with a safe entrance, at the eastern end of the 
canal, is an essential requisite to its proper operation. No such harbor 
now exists. About fifty years ago there was a good harbor at Grey- 
town, with 30 feet of water in the anchorage and at the entrance. 
The sand, however, that has been brought down by the San Juan 
River and deposited in the sea has closed the entrance, and in a large 
measure filled up the harbor itself. This sand movement has been 
going on for ages, as the numerous lagoons that have been formed 
parallel to the coast line testify. The sand has been ejected from 
volcanoes in the region of the headwaters of the Costa Rican tributaries 
of the San Juan, carried down to the sea by the river, deposited on 
the ocean bed, and then transported by wave action in one direction or 
the other, according to the prevailing winds and the resulting direction 
of the waves. 


INTEKOCEANIC CANAL. 


33 


By the term “harbor” it is not intended to convey the idea that a 
large harbor should be constructed for commercial purposes. A har¬ 
bor of sufficient area to accommodate the vessels that arrive for the 
purpose of passing through the canal is all that is considered necessary. 
It is not expected that vessels will lie in such a harbor for any length 
of time, but will move through, either in one direction or the other. 

For canal construction purposes a harbor is necessary. One of the 
first things, therefore, to be done in undertaking the construction of 
the canal will be to form a harbor of reasonable depth. This has an 
important bearing in estimating the cost of construction. 

The San Juan River drains a basin of about 17,000 square miles. 
The silt deposited in its delta during past ages has built out the coast, 
with characteristic lagoons and extensive marshes covering the broad 
plain between the present shore line and the original foothills of the 
Cordilleras. 

The delta may be said to begin at a point 12 miles in an air line 
from the outer coast, where the San Juanillo leaves the main trunk. 
This stream has been turned parallel to the coast, and finally reunites, 
through a series of lagoons, with the Lower San Juan. The latter is 
Hanked by lagoons indicative of original beaches, the three to the 
north being typical of the prevailing direction of the drift on this por¬ 
tion of the coast, due to the angle of wave incidence. These lagoons 
are nearly parallel to the existing coast line and are separated by strips 
of land inclosing long, narrow lakes. The date of these formations 
is not ascertainable from anv existing records. 

It would seem that what is now the Lower San Juan River was at one 
time the main stream and discharged most of the sediment, the waves 
produced by the trade winds carrying a part of the material to the 
westward and a part of it to the southward, the westerly movement 
of this sand having formed lagoons whose longer axes are nearly par¬ 
allel to the coast. The prevailing winds are from the northeastward, 
and while they rarely blow with great violence, the} r blow steadily and 
with considerable force, creating a sea which stirs up the light sand of 
which the beach is composed and carries it along in great volume. 
One has only to observe the waves charged with black sand, running 
diagonally along the beach, to realize their potent agency in trans¬ 
porting this material. 

The board of 1895 gives a very complete description of the sand move¬ 
ment on this coast, a full discussion showing how the destruction of 
Greytown Harbor as it formerly existed was brought about, and the 
steps necessary to be taken in the construction of a new harbor. The 
conclusions arrived at by that board were that the Maritime Canal 
Company’s' proposed entrance is inadmissible, and the harbor head 
entrance inexpedient, and that the best results will be obtained by 
locating the entrance approximately halfway between the two. This 
Commission is of opinion that equally good results, at less cost, can be 
obtained by a change in the entrance and form of the harbor itself. 
The Commission has, therefore, located the east jetty about 2,000 feet 
westward of the position suggested by the board of 1895, the harbor 
itself to be about 5,000 feet long by 1,000 feet wide, and the entrance 
between the jetties to be 600 feet. 

The construction of a jetty across the path of moving sand must of 
necessity cause accumulations of drift to windward; hence the angle 
formed between any such projecting structure and the shore must 

S. Doc. 264, 59-1-3 


84 


INTEROCEANIC CANAL. 


gradually fill up and the shore line advance seaward until the capacity 
of this receptacle is exhausted. This advance diminishes as the depth 
and consequent capacity of the pocket increase, but it shows that some 
expense must be incurred for the maintenance of the harbor either by 
jetty extension or by the removal of the material from time to time, 
which would otherwise find its way around the end of the jetty and 
into the channel. A study has therefore been made of the various 
surve} 7 s of the harbor with a view to determining the probable amount 
of material to be controlled in the maintenance of the entrance. This 
amount is estimated to vary from 500,000 to 730,000 cubic yards 
annually. 

The entrance to the harbor will be formed by two parallel jetties 
about 600 feet apart, the easterly one about 2,670 feet in length, the 
westerly one 2,500 feet. They will extend seaward in a northerly 
direction, thus giving shelter from the sea, which comes generally 
from the northeastward. As the sea strikes the shore line with con¬ 
siderable violence at times, these jetties will be constructed chiefly of 
heavy stones not easily moved by the force of the waves. To obtain 
suitable stone for this purpose in large quantities and with the utmost 
dispatch, so that a part at least of the jetty can be quickly constructed, 
quarries will have to be opened at the most favorable locations. 

BRITO HARBOR. 

At the westerly terminus of the canal there is no harbor. The 
nearest harbor is that at San Juan del Sur, about 8 miles to the 
southeastward, but this can not be put to any useful purpose so far as 
the canal itself is concerned, though it may be utilized in a measure 
during the early stages of canal construction. A harbor will have to 
be constructed at Brito as at Greytown. San Juan del Sur could only 
be used to advantage during construction by the building of a railroad 
from there to the canal. 

The remarks as to the capacity of a harbor at Greytown will apply 
with equal force to Brito. In other words, a harbor of refuge is not 
needed, but only such a harbor as will make the canal available for 
commerce. Vessels will seldom go to Brito unless entering or leaving 
the canal. 

The conditions on this coast are not as forbidding as the} 7 are on the 
eastern. The sand movement is slight and the winds are mostly off¬ 
shore, consequently the difficulties to be encountered will be more 
easily overcome. The mean rise and fall of tide is about 7 feet. The 
sea during the greater part of the year breaks normal to the direction 
of the shore; the prevailing wind is from the northeast, and while west 
and south winds sometimes blow, they are of rare occurrence. 

The shore is bold, and deep soundings are found at no great distance 
from it. The shore line trends from northwest to southeast, but the 
rocky promontory on the north side of the Rio Grande projects into 
the sea and gives a certain amount of protection. 

On account of the rapid increase in depth from shore seaward, an 
outer harbor is almost impracticable within the limits of reasonable 
cost, so that one is restricted to the formation of an inland harbor 
within the area that is now occupied by a swamp. From borings made 
and all information obtainable it is believed that this material is easy 
to excavate. In fact, it is known that some of the borings taken by 


1NTER0CEANIC CANAL. 


35 


the canal company in close proximity to the proposed harbor, which 
seemed to indicate rock at no great depth, were deceptive and that the 
boring apparatus struck bowlders which were supposed to be solid rock. 

The harbor proposed by Colonel Childs opened directly to the south, 
and was protected by two jetties, one springing from the sandy beach 
and running southward, the other, but smaller, jetty springing from 
the Brito promontory and running southeastward. The entrance 
was 400 feet wide. An inner harbor was formed by a change in direc¬ 
tion of the entrance at nearly a right angle, which gave good protec¬ 
tion. The size and depth of the harbor proposed would be utterly 
inadequate to the present size and draft of ships. A diversion of the 
Rio Grande to the eastward of the entrance was a necessarv feature of 
this scheme. 

Captain Lull, in his project for a harbor, made some changes in the 
Childs project, with a view to giving a wider entrance and more capa¬ 
cious and deeper harbor, suited to the increased depth which he 
proposed. 

The Maritime Canal Company also proposed a plan for a harbor, 
increasing the area to 103 acres. 

The board of 1895 suggested still another project, the main feature 
of which was the extension of the west jetty of the Lull plan to a 
length of 3,600 feet. This was, however, only provisional, with a 
view to an approximate estimate and not as a definite project neces¬ 
sarily to be followed. That board distinctly stated that u the informa¬ 
tion available is not sufficient to enable final plans and estimates to be 
made.” 

All the plans proposed have certain inherent defects, and it is 
scarcely possible to construct a harbor at this place that will be perfect. 
A breakwater to shelter an entrance becomes a very expensive struc¬ 
ture in such a place as Brito and is liable to introduce other objection¬ 
able features. 

It is believed, however, that the difficulties of a vessel’s entering 
between two jetties that project seaward in the direction of the 
advancing waves have been overestimated in the case under consider¬ 
ation. San Juan del Sur is a fairly good harbor, yet its entrance is 
open to the sea. It is said that no trouble is esperienced by shipping 
at this place from such exposure. A Pacific mail steamer calls at this 
harbor once a week throughout the year. She does not go to a dock, 
for there is none at which she could lie, but it is understood no trouble 
is experienced in lightering from her anchorage. 

To permit a vessel to enter the harbor normal to the swell and at 
the same time to guard it against agitation from the admission of large 
waves are conditions not easily satisfied, but the Commission believes 
that the form of harbor presented with this report will meet the con¬ 
ditions as nearly as it is practicable to do within the limits of reason¬ 
able cost and in a manner less objectionable than any other yet proposed. 

The plan is to build a jetty from a point on the beach about 3,600 
feet east of the Brito promontory, extending out into the sea in a 
direction nearly south-southwest to the 7-fathom curve, then exca¬ 
vate a harbor of the form shown on the plan to the eastward of a 
north and south line through the root of the jetty, the entrance to be 
600 feet wide at the throat. This will give security and comparatively 
still water in all winds except those coming from south bv west and a 
few degrees either side. The promontory will protect from winds 


36 


1NTER0CEANIC CANAL. 


coming from a more westerly direction and the jett}^ from all winds 
coming from a direction east of south. The basin to be excavated has 
a bottom area of about 135 acres and a depth of 30 feet at mean low 
tide, with a depth of 36 at the entrance. As the movement of sand is 
slight, the cost of maintenance will not be great. 

The Rio Grande in this project will not be diverted at its lower end, 
but it will have to be enlarged in cross-section in order to carry 
increased discharge. 

If the conclusions reached by this Commission, that this harbor gives 
all the protection that is needed, be found by time and experience to be 
incorrect, a jetty from the promontory eastward can be added at any 
future time. It is believed, however, that such jetty will never be 
required, and no provision has been made in the estimate for one. 

DAMS AND EMBANKMENTS. 

To construct safe, durable, and stable structures for the control of 
the drainage and for navigation is a sine qua non. 

The principal causes for the failures of dams or reservoirs may be 
traced to defective foundations, improper design, or imperfect con¬ 
struction, single or combined. Probably the most frequent causes of 
their failure are their permeability causing a breach by seepage and 
their lack of spillway capacity, allowing the dams to be overtopped 
by Hoods. 

The sites proposed in Nicaragua for the dams are such that, in con¬ 
nection with the large impounding capacity of the lake acting as a 
reservoir, there is little or no danger of sudden Hoods reaching their 
crests, so. that the risk from this source is believed to be eliminated by 
providing an ample waste way and free board. This remark applies 
with still greater force to the embankment lines, which may be used 
for the purpose of inclosing large artificial lakes in basins of limited 
drainage area and not subject to the discharge from the river. 

Moreover, there is an abundance of material suitable for puddle, 
which, if properly applied, will secure impermeability. The main 
difficulty, therefore, is that resulting from insecure foundations. For 
the dams in the rivers closing the summit level satisfactory rock bot¬ 
toms and abutments are available, but to reach rock on the San Fran¬ 
cisco embankment line is a more difficult and expensive problem. 

DAMS ON THE EASTERN DIVISION. 

In view of the large amount of earth and rock excavation and the 
necessity for disposing of the spoils, it was decided by the Maritime 
Canal Company to construct high rock-fill dams on both sides of the 
lake for the purpose of impounding the waters of the summit level, but 
the desirability of avoiding the San Carlos River and of facilitating the 
construction of the dam itself has led this Commission to select a new 
and better site a short distance above the mouth of the San Carlos 
River. 

The borings made on the site of the proposed Ochoa Dam revealed 
rock at 17 feet below sea level suitable for foundations. The width 
between banks is relatively narrow, for at an elevation of 100 feet 
above sea level it is about 1,400 feet. As this site is below the junction 
of the San Carlos River, which at hood stages it is estimated may dis- 


i 


INTEROCEANIC CANAL. 


37 


charge 100,000 cubic feet per second, in addition to the lake and San 
Juan River drainage, this large volume must either be disposed of over 
spillways on the San Carlos ridge or be allowed to waste over the dam 
itself. Its sediment also would be deposited in the bed of the stream 
above the dam and cause constant shoaling. At lower Ochoa the sand 
extends to 30 feet below sea level. To avoid these serious objections, 
as well as to eliminate if possible the embankments of the San Fran¬ 
cisco and Florida lagoons, examinations were made for a dam site at 
Tambor Grande Island. The subsequent borings in the bed of the river 
at this site, however, showed an erosion of the bed rock extending to 
128 feet below sea level, which would necessitate a dam in this narrow 
gorge of the river nearly 250 feet in height, subject to the How of the 
entire drainage basin. This project was therefore discarded. 

The more recent examinations and surveys, made on the wider reach 
of the river above the San Carlos, gave results which were quite satis¬ 
factory. Here the flowage line is almost continuous, requiring but one 
small embankment, while the section affords ample weir length. Good 
solid rock foundations exist at about 15 feet below sea level. Thus, 
the maximum height of the dam from the bottom of the foundation 
would be 138 feet. The construction of a dam at this point avoids the 
serious objections to the Ochoa site, and also reduces the cost and diffi¬ 
culties of construction. 

The estimates are based upon concrete, which can be mixed on the site. 
Regulating works and sluices can be provided in the original river 
channel, and the entire length of the crest may be utilized for a spill¬ 
way in case of necessity. 

The typical section on which the estimates are based is the ogee rising 
from the natural bed of the stream at an elevation of about 38 feet 
above sea level to the proposed weir sill at 98, with regulating sluices 
to control the higher stages. The width of the base at the deepest 
point is 100 feet. The ordinary stage of water at the foot of the dam 
is about 55 above sea level, while extreme low water is about 45. 

SITES FOR LOW DAMS. 

There are various locations on the river where dams may safely be 
placed for variations of project. Taking these in order, coming down 
stream, the first may be at Castillo , where the river flows over ledges 
of basalt which is somewhat jointed, giving it the appearance of being 
stratified, but it is believed to be firm and strong. The anchorages 
also are good. 

At Upper Machuca , 3 miles above Machuca, the rock is calcareous 
sandstone, with limited weathering. Solid rock is usually found under 
a few feet of* sand in the river channel, but the rock in the adjacent 
hills is weathered down nearly to the same level as the surface of the 
solid rock in the channel, so that the anchorage must be in residual 
clay and soft rock. 

The Machuca site is situated across the head of Campana Island. It 
is based on a fine-grained light-bluish gray rock, evenly bedded, and 
closely resembling a fine-grained quartzite. The borings on the south 
banks, however, show great depths of weathering, making it desirable 
to shift the location farther up or down stream. 

Conchuda , about 2 miles above the Boca San Carlos, also affords a 
possible dam site, and has been considered with a view to reduce the 


38 


INTEROCEANIC CANAL. 


large amount of rock excavation incidental to the Machuca dam 
projects. 

Relative cost of the several concrete dam projects between the lake and Boca San Carlos , 

including the latter. 

[These estimates are based upon the same prices in each case, and are submitted merely as a guide to 

the relative merits of the plans.] 


Low dam at Upper Machuca.-.$1,045, 569 

Low dam at Lower Machuca. 866, 040 

Low dam at Boca San Carlos. 2,633,124 


4,544, 733 


Low dam at Lower Machuca. 1,240, 785 

Low dam at Conchuda. 2, 721, 411 

Low dam at Boca San Carlos.. 2,633,124 


6, 595, 320 

Both of the above schemes would require in addition a large amount 
of rock excavation in the river to create navigable channels in the 
pools, which would be avoided by the higher single dam. 

High dam at Boca San Carlos, of concrete, $4,570,340. 

SAN CARLOS AND SAN FRANCISCO EMBANKMENT LINES. 

The hills to the southeast of the San Carlos River contain depressions 
which would have to be closed by earthen embankments to provide for 
the Menocal project, with weirs through the saddles. The depth to 
hard rock varies from probably 60 to 100 feet, but as the San Carlos 
embankments will be avoided by the change of the dam site to a point 
above the Boca San Carlos, no further discussion of its embankment 
line is required. It would be necessary, however, to extend the San 
Francisco embankment line from Ochoa up the left bank of the river 
to connect with this new location, involving heavy work. 

EMBANKMENT FOUNDATIONS. 

To ascertain the character of the material underlying the proposed 
embankments crossing the Florida, San Francisco, Nicholson, and Chan- 
chos depressions deep borings were made in each, which revealed the 
residual clay and soft rock beneath the alluvium but in thinner strata 
than on the hills. 

“The rock is only moderately hard, consisting chiefly of talcose vol¬ 
canic tuff, with a thin bed of earthy limestone.” The silt in these 
depressions and swamps apparently extends to about ten feet below 
sea level and renders it desirable to reduce the height of the embank¬ 
ments as much as possible. All the routes traverse the reach on the 
left bank of the San Juan from Boca San Carlos to the San Francisco 
near its mouth and hence cross these lateral tributaries, but at differ¬ 
ent elevations, dependent upon the number and location of the locks. 

DAMS ON THE WESTERN DIVISION. 

THE LA FLOE SITE. 

Much has been said pro and con concerning the possibility of con¬ 
structing a dam at this site, and the board of 1895, basing its conclu- 












1NTER0CEANIC CANAL. 


39 


sions upon certain exhibits as to geological structure, declared it 
inexpedient, in view of the slight advantages and the ability to con¬ 
struct a canalized channel at a somewhat greater cost on the left bank 
of the Rio Grande. 

In the light of more recent borings and their interpretation by Dr. 
Hayes, this Commission is of opinion that a dam at this point is prac¬ 
ticable. 


BUEN RETIRO. 

The summit level would terminate at Buen Retiro, about 9 miles 
from the lake, where the topography is well adapted for the purpose, 
as it affords opportunities for spill wa}^s directly into the bed of the 
Rio Grande and Guachipilin, and for a good lock site. Here a small 
ovoidal hill rises from the bottom of the valley 44 composed of a cal¬ 
careous shale more or less disintegrated, but sufficiently firm for foun¬ 
dation purposes.” The rock is about 50 feet above sea level, and 
comparatively little silt would have to be excavated to place the foun¬ 
dations. The regulating works with the lock will close the summit 
level, making it unnecessary to build a dam at this site. 

No other dams are required on the west side under any of the 
variants. 


CANAL LOCKS. 

On the route selected as a basis for the estimate it is proposed to 
construct six locks of 18.41 feet Mft each on the eastern division, giv¬ 
ing a total of 110.46 feet, and four locks of 29 feet lift each on the 
western division, giving a total of 116 feet, the difference of 5.54 feet 
being due to the difference in rise of tides in the two oceans. 

In estimating the cost of the locks the large Poe lock at the Sault 
Ste. Marie Canal at the outlet of Lake Superior was taken as a stand¬ 
ard, and the dimensions of lock chamber, fore and tail bays, gates, 
culverts, etc., were modified to adapt them to the present require¬ 
ments. The lock pits were extended to 15 feet below the floor to pro¬ 
vide for the culverts and valves and the necessary foundations. The 
following are the dimensions used for one of the 18.41 feet lift locks: 


Feet. 

Number of culverts...-. 4 

Length of floor and side walls. 939. 5 

Width of floor in the clear. 80 

Height of side walls = lift -f- draft -f- 4 feet. 52. 41 

Length of sides between abutments. 601. 75 

Width of side walls at top. 10 

Width of side walls at bottom. 21. 53 

Width of abutment walls at quoins. 31. 77 


On the western division the topography is such that the best results 
are obtained by the use of four locks having the same dimensions as 
to length and breadth, the only modification being in the lift and thick¬ 
ness of the walls and foundations. 


Upon this basis the six locks on the eastern division will cost.$9, 560, 400 

The four locks on the western division will cost. 7,412, 580 

Making the total cost.-.-. 16,972, 980 














40 


interoceanic canal. 


QUANTITIES. 

The general advantages and disadvantages of the several locations 
have already been stated under the head of “ Projects and routes,” but 
no final location nor estimate could be completed until after the quan¬ 
tities of the different classes of material on the several routes had been 
determined. 

Asa large number of variants are possible, particularly on that part 
of the route lying between Boca San Carlos and the sea, and as it was 
impossible to determine before the preliminary surveys were com¬ 
pleted and platted which would give promise of the best results, the 
detailed geological examination by borings on any specific route had 
to be deferred for a later date. The classification which has been 
made along these low level routes is therefore based upon outcrops, 
borings by the canal company confirmed b}^ the Commission at a few 
points, and an examination of the region, which is believed to be 
ample for the purpose of an estimate. 

The collection, platting, and computing of these data have required 
considerable time, but so far as quantities are concerned they are 
quite reliable. There may be variations in the classification where 
the lines of separation between different materials merge into one 
another, but they will be more or less equalized, so that errors due to 
this cause will be small. 

For more convenient reference and comparison of the quantities 
under the variations of line and grade they have been arranged in a 
table a which gives the amount of excavation and embankment in each 
division and for each project and class of material, excepting for the 
harbors, railroad, and dams. The cost of the dams, locks, weirs, and 
other structures is given in the item entitled “Auxiliary cost” 
appended to each division. 

By the aid of this tabular statement of quantities an estimate of the 
cost of constructing the canal trunk may readity be obtained by apply¬ 
ing any suitable unit price to the factors as stated. The amount of 
dredging for the two harbors not included in the table, which should 
be added to the totals is, for Greytown, 10,748,900 cubic } T ards, and 
for Brito, 9,500,000 cubic yards. The jetty and other harbor work 
is not included in the table, but is stated in the estimates. 

For the route recommended by the Commission, passing to the north 
side of Silico Lake, following the left bank of the San Juan and Rio 
Grande rivers, and having a bottom width of 150 feet, with ten locks 
and one dam, the quantities from ocean to ocean, exclusive of the rail¬ 


road, are: 

Cubic yards. 

Dredging, river and coastal plain. 61, 738, 842 

Dredging, lake and harbors. 37, 557, 750 

Earth excavation and embankment. 29,907, 996 

Disintegrated rock. 15, 248, 312 

Solid rock. 7, 573,992 

Rock under water. 754, 378 


UNIT PRICES. 


152, 781,270 


The Commission has endeavored to reach conclusions in respect to 
the probable cost of the canal that will be fair and just. It has tried 


a See ‘ ‘ Table of quantities ’ ’ in Atlas. 












INTEROCEANIC CANAL. 


41 


to have the figures represent the probable cost of the canal as nearly 
as can be ascertained, without being too high or too low. It must be 
admitted, however, that any estimate of probable cost is to some extent 
a matter of judgment. It is not possible to determine this matter with 
absolute certainty, as many of the elements on which one’s judgment 
would be based are not accurately known. One’s experience in like 
work, and the experience of others, are the only guides. There has 
never yet been a work of similar character executed under exactly 
similar conditions, and it should be remembered that work on a small 
scale, or which is greatly distributed and not en masse, involves more 
loss of time and labor and is consequently more expensive. The work 
on the Panama Canal would perhaps come near it in some respects, 
but no one would think of comparing the extravagant methods which 
characterized the early history of that enterprise with the methods 
that should be employed on this. 

The latest work of magnitude of this character which affords to 
some degree a means of comparison is the Chicago drainage canal. 
The total excavation for this work amounted to about 12,318,000 cubic 
yards of rock and 26,087,000 cubic yards of earth, a total of 38,405,000 
cubic } T ards, of which about 10 per cent was dredging. The earth was 
of every variety from soft mud to hard, indurated clay with bowlders, 
all being included under the name of “glacial drift.” The rock was 
the Joliet limestone, stratified in nearly horizontal layers, and is 
described as ideal for ease in excavation. The proportion of rock to 
earth is less in Nicaragua than in the Chicago drainage canal. The 
actual average price paid for excavating “glacial drift” at Chicago was 
29 cents per cubic yard. The average cost of rock was 77 cents. If 
the Nicaragua Canal were located near Chicago and its rock and earth 
similar in character to those of the Chicago drainage canal, it is prob¬ 
able that the average cost for earth excavation would be the same in 
each. The earth in the Nicaragua Canal varies in character from stiff, 
indurated clay to diluted silt. The range is equally wide in the Chi¬ 
cago drainage canal. It can not be asserted that the earth is alike in 
the two places, but it is believed that it may be substantially so. Under 
such circumstances it might be fairly assumed that the average cost of 
earth excavation, if the canal were located near Chicago, would be 29 
cents. 

As the Chicago drainage canal affords the' nearest precedent avail¬ 
able and as the actual average prices of that work have been taken as 
a basis, it is necessary to state the classification of the material as 
specified for that work, which was as follows: 

For the purpose of letting the contracts the material to be excavated was divided 
into two classes, rock and'“glacial drift.” The first term explains itself, but the 
character of the material termed “glacial drift,” this being an entirely arbitrary 
classification, needs some further explanation. As defined in the specifications, 
“glacial drift shall comprise the top soil, earth, muck, sand, gravel, clay, hard pan, 
bowlders, fragmentary rock displaced from its original bed, and any other material 
that overlies bed rock.” In fact, all these materials are found in all degrees of inter¬ 
mixture, from soft black muck, which can be pumped with centrifugal pumps, to a 
conglomerate of sand, gravel, clay, and bowlders cemented together with almost the 
hardness of rock, and only to be excavated by means of the strongest steam shovels, 
and sometimes even requiring blasting to break it up. 

In Nicaragua the rock on the western division is chiefly a calcareous 
shale, thinly stratified and much broken. Some pits of considerable 
depth have been excavated without blasting, and the rock has been 
used for macadamizing the roads. It is believed that a large part of 


42 


INTEROCEANIC CANAL. 


this rock could be excavated with steam shovels without blasting. It 
is drilled slightly easier than the Chicago limestone and is more brittle. 
The location of the spoil banks would be quite similar to that of the 
Chicago work. It is therefore probable that some of this rock could 
be excavated for a price slightly cheaper than the Chicago rock. Some 
of it, however it is known, will cost more. It is probable that, taken 
as a whole, it could be done for the same price, and it is so assumed. 

Between Lake Nicaragua and the Caribbean Sea, viz, the eastern 
division, the rock is basalt, dacite, sandstone, and volcanic tuft*. The 
basalt and dacite are both considerably harder to drill and blast than 
the Chicago limestone. In the larger cuts the waste material will have 
to be transported some distance to the dumping grounds. For these 
reasons it is estimated that the cost per yard will be increased 10 cents. 
Therefore it is assumed that if the Nicaragua Canal were located near 
Chicago the cost of excavating its rock would be 87 cents per cubic 
yard on the eastern division and 77 cents per cubic yard on the western 
division. 

With reference to the actual work at Chicago, Mr. Isham Randolph, 
the present chief engineer of that work, writes as follows: 

The prices on our work ranged from 59 cents to 80 cents for solid rock and from 
19.9 cents to 56 cents per cubic yard for glacial drift. This glacial drift, however, 
covered material which under railroad specifications would come under the heads of 
loose rock and hardpan. The average price paid on this work per cubic yard was 
for solid rock, 77.3 cents, for glacial drift, 28.7 cents. * * * 

In the light of our experience, I believe that a work of like magnitude prosecuted 
under similar conditions could be put under contract at a reduction of about 15 per 
cent from our ruling prices; in other words, that rock work should be done for 65 
cents and earth for 24£ to 25 cents, which prices would, I believe, provide a fair 
margin of profit for the contractor. 

Mr. Lyman S. Cooley, former chief engineer and director of this 
work, also concurs in this opinion, stating that some very hard glacial 
drift was removed for 26 cents per cubic yard and that the actual cost 
of rock work was about as follows: 

Cents per 
cubic yard. 


For plant. .15 

For loading. 15 

For hoisting. 15 

For channeling. 5 

For drilling. 6 

For explosives. 8 


Total. 64 


Including contractor’s profits. 

It yet remains to assign the relative cost of work in the United 
States and in Central America. This will involve greater uncertainty, 
for the reason that there have been no large works in Central America 
with which comparison could be made. There has, however, been 
some railroad building in all of the Central American States, often in 
amount sufficiently large to require the importation of labor, thus 
making the conditions of labor similar to those which would obtain if 
the Nicaragua Canal should be built. 

Mr. William H. Keith, contractor, reports the cost of work on the 
National Railway of Costa Rica to be for solid rock 60 cents in gold 
per cubic yard, for loose rock 30 cents in gold per cubic } r ard, and dry 
earth 18 cents in gold per cubic yard; concrete in place, including 
“ forms,” $9 per cubic yard. 










INTEROCEANIC CANAL. 


43 


Mr. Louis Wichmann, general manager of the Atlas Company, who 
has been engaged in building a railroad, 6J miles in length and 2£ feet 
gauge, from Grey town to the Lower San Juan River, states “that the 
total cost per cubic yard of - excavation on the Silico Railroad is $1.25 
Nicaraguan currency, equal to 50 cents gold.” 

In explanation of this abnormally high price, he says that— 

The disadvantages were extremely bad weather, especially in June and July, dur¬ 
ing which time we had some seven weeks of continuous rain, and the principal part 
of the material being heavy clay it was very difficult to handle. 

Being entirely without mechanical appliances I had to rely on manual labor, 
which, considering the nature of the soil and constant downpour of rain, has proved 
a great drawback. 

The material on the first big through cut at the Silico end consisted of conglom¬ 
erate with large round bowlders, which could only be removed after blasting, and 
unfortunately, owing to the Spanish-American war, we were unable to secure 
explosives at the time when they were most needed. 

Other difficulties mentioned were the long carriage to the spoil 
banks and the fact that all supplies, tools, and provisions had to be 
transported on the backs of the laborers. 

These conditions and prices can not therefore be cited as being com¬ 
parable to the probable cost of so great a work as the construction of 
this canal, where the most modern appliances should be used. 

Quite recently it is credibly stated that the Silico Railroad had cost 
more than was anticipated, and that the total cost was from $110,000 
to $120,000, length 6£ miles, equivalent to $16,923 to $18,461 per mile, 
and that this cost included everything—roadbed, rails, rolling stock, 
bodegas, wharves, and all terminal facilities at both ends. It was 
built in very bad weather and under great difficulties. The rolling 
stock consists of 1 locomotive, 8 freight cars, 2 construction cars, and 
2 passenger cars, which were imported. The ties on this road were 
furnished and put in place for about 24 cents apiece in gold. 

The cost of excavation varied from 50 cents to $1 (Nicaraguan currency) per 
cubic yard, depending upon the condition of the weather and the labor. During 
the early part of the construction Fortune Island negroes were employed, but were 
found unsuitable for the work. While these men were employed the cost of exca¬ 
vation was rather high. The labor now consists of natives and Jamaicans, and the 
cost of excavation is kept below 70 cents. 

The cost of food for each man per day varied from 52 cents to 75 cents. This is 
included in the cost of excavation. The material chiefly excavated was blue and 
brown clay. In handling the blue clay the rains had no effect upon it whatever. 
The brown clay becomes rather difficult to shovel when wet, as it has a tendency to 
stick. In the former the same amount of material can be hauled on a wet day as 
on a dry day. The haul in some cases was over 400 feet. During rainy days the 
work was not interrupted. 

The rate of exchange at present is 200 per cent premium. 

An engineer of large experience in Guatemala states that prices for 
grading on railroad work in that country were as follows: For earth, 
from 30 to 40 cents; for loose rock, from 65 to 85 cents, and for solid 
rock, from $1.40 to $1.75, exclusive of cost of administration and en¬ 
gineering. The prices paid for clearing ranged from $65 per acre on 
the swamp work to as low as $25 for the upper end of the line. The 
cost of masonry, where the haul was less than half a mile, was about 
$24 to $28 for first class, $14 to $18 for second, and $10 to $12 for 
third. “ In all of the foregoing, prices are expressed in the silver of 
the country.” The rate of exchange is not stated. 

Another engineer, also in Guatemala, states that the unit prices there 
were for earth 40 cents, telpetate $1, loose rock $1.25, solid rock 


44 


INTEROCEANIC CANAL. 

$1.80; masonry exclusive of cement, third class $10, second class $16, 
and first class $25 per cubic }^ard. “ These prices include a good 
profit if work is properly handled.” They are all on a silver basis. 
Converted into gold at the Nicaragua ratio they would be: For earth, 
16 cents; telpetate, 40 cents, loose rock, 50 cents; solid rock, 72 cents; 
third-class masonry, $4; second-class, $6.40; first-class, $10. 

Mr. M. P. Carter, civil engineer on the construction of the Cauca 
Railroad in Colombia, where the rainfall is said to exceed 300 inches 
a year, testified under oath that u a man working in earth work would 
move 3 or 4 yards a day at 40 cents a yard; that is the average. For 
loose rock, that has been loosened a little with a pick, he might move 
li or 2 yards a day at 80 cents a yard, and for conglomerate a man 
would not move more than two-thirds or three-quarters of a yard 
per day at $2.20 per yard.” All of the above prices are in Colombian 
money, which would make the equivalents in gold for earth 17.2 cents, 
for loose rock 34.4 cents, for conglomerate 92 cents. 

[Extract from a letter from Mr. Harold R. Miller, dated Atlas Line of Mail Steamers, New York, 

April 22, 1899.] 

The three rates for earth work and conglomerate were 40 cents, 80 cents, and $2.20, 
Colombian, as per Mr. Carter’s evidence. The exchange at that time was 180 to 150, 
say 140, per cent. That makes 17 cents, 34 cents, and 92 cents gold. To-day the 
exchange is 230 per cent, viz, $1 gold is $3.30 Colombian. Labor, of course, has not 
risen in proportion with the exchange, so that construction work is really cheaper 
to-day than then, because contractors get more currency for their gold and pay about 
the same rates. Labor is about $1 Colombian in the interior, $1.40 to $1.60 on the 
coast. The conditions on the Isthmus are different from the rest of the Republic, 
owing to the silver currency, which alone prevails on the Isthmus. The rest of the 
Republic uses paper, which has about 20 per cent discount as compared with silver.- 

[Extract from communication, dated October 30, 1887, from Edwin F. Smith, civil and hydraulic 

engineer.] 

In conclusion, I desire to say that processes of dredging have improved very much 
in recent years, and large companies in the United States w r ould, I think, be found 
willing to take such contracts at Greytown, and on the line of the Nicaragua Canal, 
at less than the figures given in the estimates of the canal company. 

This is true not only of dredging, but also of rock excavation. There are con¬ 
struction companies and contractors handling material on the Chicago Drainage Canal 
with modern appliances who would, no doubt, eagerly compete for such contracts as 
those of the rock cut through the Eastern Divide and the building of the Ochoa 
Dam, and the dredging of Greytown Harbor and the canal through the lagoons. 

[Extract from a communication from Col. T. P. Roberts, chief engineer Monongahela improvement.] 

On the Nicaragua Canal, if extra prices are paid foremen and bosses, the actual 
cost of work will not be much in excess of that for which it could be done here. A 
general increase of 25 per cent over American prices ought to be sufficient. While 
I would thus suggest a reasonable unit price for items of labor, I would advise a 
liberal percentage on the whole work, to cover engineering and managment. Admin¬ 
istration expenses will doubtless be very high at first, but this item wfill diminish 
after the officials have become acclimatized. Physiciansand sanitary engineers should 
be employed to select the places for camps, provide the water supply, and look after 
the drainage. If this be properly done, the cost for hospital service would not be 
great. I do not see why this item should be differentiated. * * * A millage tax 
on all salaries and wages should be fixed to maintain hospitals. 

It has been my observation for several years past that American engineers have 
been overestimating the cost of work. They appear to me to not fully realize the 
wonderful improvements which have been made in this country. Many of them 
still think that French and German methods on canal w r ork admit of little improve¬ 
ment, but such engineers have not been attentive students of the Chicago Drainage 
Canal experience. 

In July of this year six locks and dams were let on the Monongahela River. The 
United States engineers’ estimate for them all was about $1,200,000, which amount 


1NTER0CEANIC CANAL. 


45 


I thought was about the right thing, but, although the estimate was publicly known, 
a number of responsible contractors bid less than $800,000, and it was actually 
awarded for less than $700,000. The bidder failing to secure bondsmen, the Depart¬ 
ment ordered another letting. 


For convenience of comparison these prices are tabulated as follows: 



Earth. 

Loose 

rock. 

Solid 

rock. 

Chicago basis. 

29 


77 

Costa Itica. 

18 

30 

60 

Guatemala. 

14 

30 

63 

Do. 

16 

50 

72 

Colombia. 

17 

34 

92 


Average. 

161 

36 

71f 




From this it appears that the actual cost of earth work in these 
tropical countries is in general less than that given for the Chicago 
basis. The average for earth and loose rock is 26 cents, which is less 
than the Chicago price of 29. The average of the rock work is also 5 
cents below that at Chicago, so that it would seem that the statement 
of Mr. Shunk, chief engineer of the Intercontinental Railroad Com¬ 
mission, is apparently correct that “an estimate of like work at home 
would be fairly applicable down there.” 

In view, however, of the difficulties of securing a sufficient supply 
of laborers for so great a work, and of regulating their wages, the 
Commission has concluded to increase the actual average prices paid 
at Chicago by 33 i per cent for all earth and rock work on the western 
division, and by 50 per cent for work on the eastern division, after 
allowing an increase of 10 cents for rock on the eastern division 
because of local differences and character of material. 

The prices applied to the quantities will therefore be as follows: 

t 


ON THE EAST SIDE. 


For Grey town Harbor, dredging.per cubic yard.. 

For Greytown Harbor, jetties.do- 

For dry earth excavation.do- 

For solid rock excavation.i.do- 

For dredging in upper river.do- 

For dredging in lake.do- 

For rock under water.do- 

Timber cribs.do- 

Clay puddle and back filling, exclusive of cost of excavation....do- 

Concrete in structures other than locks.do- 

Concrete in locks.do- 

Stone pitching on embankments.per square yard.. 

Timber in structures.per M. B. M.. 

Clearing.-.per acre.. 

Clearing and grubbing.do- 


$0. 25 
2.50 
.44 
1.30 
.30 
.20 
5.00 
3.25 
.50 
8. 30 
7.23 
2.00 
60.00 
75. 00 
100. 00 


ON THE WEST SIDE. 

For dry earth excavation.per cubic yard.. 

For solid rock excavation.do- 

For dredging harbor.do- 

For rock under water.do- 

For jetties.do- 

Timber cribs.do- 

Clay puddle and back filling, exclusive of cost of excavation.do- 

Concrete in structures other than locks.do- 

Concrete in locks.do.... 

Stone pitching on embankments.per square yard.. 

Timber in structures.P er M. B. M.. 

Clearing.. .per acre.. 

Clearing and grubbing.do- 


.39 
1.03 
.20 
5. 00 
2.00 
3. 00 
.50 
8. 30 
7. 23 
1.75 
60. 00 
75. 00 
100.00 














































46 


INTEROCEANIC CANAL. 


The prices for structural work of locks and weirs are based on the 
cost of similar work in the United States, to which 33 per cent has 
been added for difference of location, including climate, etc. 

FEASIBILITY. 

Under this' division of the subject the Commission would respect¬ 
fully submit that it has failed to find any competent authority that 
denies the feasibility of constructing a canal across Nicaragua. 

The feasibility of the canal is conceded for the following reasons: 

1. There are at this date sufficient precedents for ship canals capable 
of passing the largest vessels, so that any question of the navigation 
of such a channel is eliminated. 

2. The ability to construct and operate locks of the requisite dimen¬ 
sions is sufficiently established by existing structures on the Man¬ 
chester and Keil canals, at Davis Island on the Ohio, and at the St. 
Marys Canal, Michigan. 

3. The possibility of constructing the necessary dams, weirs, sluices, 
and embankments, which shall be sufficiently stable and impermeable 
to control the water required for navigation, as well as to regulate the 
floods, is within the resources of the engineering profession and is fully 
demonstrated by the many hundreds of miles of embankments, levees, 
and dams, both at home and abroad. There is no reason to doubt the 
ability to build them out of the native rocks and earth and to give them 
the required strength and tightness to retain or to discharge the water 
with safety. 

4. There is no question as to the adequacy of the supply of water 
for all purposes at all seasons nor as to its control in times of flood. 

5. Neither is there any doubt with reference to the ability to secure 
good supporting ground for the trunk of the canal nor suitable sites 
for locks and dams. 

6. The harbor question is only a matter of money, and it is believed 
that good, capacious, and safe artificial harbors can be created at a 
reasonable cost. In brief, this Commission sees no reason to doubt 
the entire feasibility of the project, but it realizes the necessity of 
exercising due care in the preparation of the specifications and in the 
conduct of the work, that the details of construction be thoroughly 
inspected and properly executed under competent supervision. 

ESTIMATE. 

After a careful analysis and comparison of the physical features and 
quantities affecting the numerous variants, the Commission has selected 
that route which it believes will give the best results. 

This route, starting from the harbor at Grey town, crosses the coastal 
plain, passes to the north of Lake Silico, and up the left bank of the 
San Juan to the dam at Boca San Carlos, thence follows the improved 
river channel, crosses the lake, and traverses the valleys of the Lajas 
and Rio Grande to Brito, on the Pacific. 

It is characterized b}" six locks on the eastern division, having a lift 
of 18.41 feet, all lying east of the dam, and four locks on the western 
division, having a lift of 29 feet. The summit level extends from the 
lock 0.43 of a mile east of the beginning of the cut at Boca San Carlos 
to the lock 1.86 miles west of Buen Retiro, a distance of 139.3 miles. 


INTEKOCEANIC CANAL. 47 

The details of the estimates are stated in the reports of the assist¬ 
ants hereto appended, and it will suffice here to summarize and classify 
the quantities for the excavation of the canal trunk and to affix their 
unit prices in order to ascertain the approximate cost. The auxiliary 
works have also been computed for each subdivision separately and in 
detail, but the totals only are stated in this connection. The calcula¬ 
tions are based upon a minimum elevation of 104 for the summit level, 
with a depth of 30 feet and a minimum bottom width of 150 feet, asset 
forth more particularly under the “Dimensions of the canal.” 


General estimate of cost. 


Classification. 


East side, with 50 per cent over Chicago prices for earth and 
rock: 

Earth. 

Rock. 

Rock under water. 

Dredging (harbor). 

Dredging (lake). 

Dredging river and canal. 

Dredging upper river. 


West side, with 83} per cent over Chicago prices: 

Earth. 

Rock. 

Rock under water.. 

Dredging harbor. 


AUXILIARY WORKS. 


Jetties, Grey town 
Jetties, Brito. 


Concrete dam and regulating works at Boca San Carlos 

4 locks on west side, 28 feet lift. 

6 locks on west side, 18.41 feet lift. 

Weir on west side, Buen Retiro... 

Weirs on east side below San Carlos. 

Clearing and grubbing (7,463 acres). 

Guard gates, timber piers, piling, etc. 


Cubic yards. 

Price. 

Amount. 

23,206,836 
1,309,375 
472,705 
10,748,900 
17,308,850 
46,555,742 
15,183,100 

$0.44 

1.30 

5.00 

.25 

.20 

.30 

.39 

$10,211,007.84 
1,702,187.50 
2,363,525.00 
2,687,225.00 
3,461,700.00 
13,966,722.60 
5,921,409.00 

114,785,508 


40,313,846.94 

21,949,472 
6,264,617 
281,673 
9,500,000 

.39 

1.03 

5.00 

.20 

8,560,294.08 
6,452,555.51 
1,408,365.00 
1,900,000.00 

37,995, 762 


18,321,214.59 

152,781,270 


58,635,061.53 

550,000 
144,107 

2.50 

2.00 

1,375,000.00 
288,214.00 



1,663,214.00 


4,570,340.00 
7,412,580.00 
9,560,400.00 
1,102,300.00 
207,890.00 
615,625.00 
1,089, 343.00 


24,558,478.00 


MISCELLANEOUS. 


84,856,753.53 


100 miles of railroad for construction purposes, at $50,000 per mile (double track).... 

Sanitary and police. . .-....-. 

For maintenance of harbors during construction of canal, and for buoys, beacons, 
and lighting. 


Engineering and administration, 6 per cent 


General contingencies, 20 per cent 
Total. 


5,000,000.00 

2,000,000.00 

1,000,000.00 


92,856,753.00 
5,571.405.00 


98,428,158.00 
19,685,632.00 


118,113,790.00 


For the cost of engineering and administration an estimate of 6 per 
cent has been made. This estimate is large, but in a work of such 
great importance the engineering and superintendence must be thor¬ 
oughly and carefully done by men of ability and integrity, who will 
necessarily command higher rates of pay than would be deemed suffi¬ 
cient in the United States. 

























































48 


INTEROCEANIC CANAL. 


An estimate of 20 per cent for contingencies has been made. It is 
intended to cover all items of expense due to unforeseen accidents or 
emergencies. Owing to the extent and character of the work, there 
are more uncertainties than usual, including that of labor, which will 
have to be largely imported from the islands of the West Indies and 
from our Southern States. No work of this character and importance 
has ever been completed within the Tropics. There is therefore 
nothing to serve as a precedent or guide for the proper contingent 
percentage, but after careful consideration and with a desire to make 
an ample allowance, the board has decided to include an estimate of 
20 per cent, which is believed to be quite sufficient for all probable 
accidents or emergencies. 

It is believed that if honestly and properly administered, with money 
at command as required, the canal can be built within the limits of the 
above estimate. 

CONCLUSIONS. 

The Commission after mature deliberation has adopted and estimated 
for the route from Brito to Lake Nicaragua, called Child’s route, 
variant No. 1, and from the lake to Greytown, that called Lull route, 
variant No. 1. This line leaving Brito follows the left bank of the 
Rio Grande to near Buen Retiro, crosses the Western Divide to the 
valley of the Lajas, which it follows to Lake Nicaragua. Crossing the 
lake to the head of the San Juan River, it follows the upper river to 
near Boca San Carlos, thence, in excavation, by the left bank of the 
river to the San Juanillo, and across the low country to Greytown, 
passing to the northward of Lake Silico. It requires but a single dam, 
with regulating works at both ends of the summit level. 

The new location selected for the dam at Boca San Carlos eliminates 
one of the most serious engineering difficulties by avoiding entirely the 
San Carlos River with its torrential floods and large volume of sedi¬ 
ment, and by locking down immediately from this dam the difficulties 
and risks of the high embankments of the Menocal line are also avoided. 

Instead of the dam at La Flor a lock and regulating works have 
been substituted at Buen Retiro, where the topography is well adapted 
for the purpose. It is also proposed to divide the surplus waters of 
the lake basin between the east and west sides, thus reducing the veloc¬ 
ities in the San Juan and securing ample waste-way capacity for the 
maximum discharge that can ever occur, if stored and distributed over 
a short period of time. Ample provision has also been made for a 
possible fluctuation of the lake of 6 feet or more wdthout injury to 
property, by fixing the elevation of the bottom of the canal sufficiently 
low to cover seasons of minimum rainfall. The surveys have in general 
revealed better physical conditions than were hitherto supposed to 
exist, especially as to the amount of rock in the upper river, whereby 
it is possible greatly to reduce the estimated cost of construction. This 
fact will account largely for the comparatively moderate amount of the 
estimate when the enlarged dimensions of the project are taken into 
consideration. Other reductions are due to the improved methods and 
machinery available, as developed on the Chicago Drainage Canal, and 
which can not be ignored in discussing a work of this magnitude. 

The creation of sufficiently capacious interior harbors presents no 
unusual difficulties, and they can be secured at a reasonable cost. 

The field work, under the authority of this Commission, has been 


INTER0CEAN1C CANAL. 49 

carefully and well done, and is believed to be all that is necessary for 
the preliminary location of a canal, and to determine, within narrow 
limits, the final location of dams, locks, and other constructions. 
Should a canal across Nicaragua he authorized, it will be necessary to 
make further minute and careful investigations by borings to deter¬ 
mine the exact location of locks and dams, for which this Commission 
had neither the time nor money, nor would it have been justified in 
doing work of this character until the construction of a canal was 
assured. The computations of amounts to be excavated have been 
carefully made and checked to guard against errors, and are believed 
to be accurate within narrow limits. All possible information has been 
sought with regard to cost of similar work in the United States and in 
Central America, and a careful comparison made of the probable differ¬ 
ence between Nicaragua and the United States. 

To determine the proper unit prices for excavation the average of 
prices actually paid to contractors on the Chicago Drainage Canal, which 
represent cost of plant, prices paid for work done, and contractors’ 
profits, were taken. Up to this point the Commission dealt only with 
facts. To, the prices paid at Chicago certain percentages have been 
added for the difference in location, climate, etc. These percent¬ 
ages are, of course, a matter of judgment, upon which men may hon¬ 
estly differ. But from all the information obtainable by this Com 
mission and after careful consideration, with a desire to arrive at a 
proper conclusion, those used in the estimate are deemed fair and rea¬ 
sonable. 

In obtaining the estimate for cost of locks the prices actually paid 
for building the Government locks at the Sault Ste. Marie were taken, 
and 33 per cent was added for the difference of location. This per¬ 
centage is believed to be ample, as a large part of the expense of con¬ 
structing the locks will be for material, much of which can be furnished 
in Nicaragua at the same or onty a small advance upon the prices in 
the United States. 

After giving due weight to all the elements of this important ques¬ 
tion and with an earnest desire to reach logical conclusions, based upon 
substantial facts, the Commission believes that a canal can be built 
across the isthmus on this route for a sum not exceeding that stated in 
the estimate. 

The dimensions of the canal proposed are much larger than any 
hitherto considered, and will be ample not only to meet the present 
requirements of commerce, but also for many years to come. A navi¬ 
gable channel of smaller dimensions than those proposed, only sufficient 
for present needs, can be constructed for a lesser sum if deemed 
expedient. 

We have the honor to be, sir, your obedient servants, 

J. G. Walker, 

Rear-Admiral , U. 8. Navy , President of Commission . 

Louis M. Haupt, 

Civil Engineer , Member . 

In appending my signature to this report, I desire to state that I 
concur generally with the views expressed, but my estimate of the 
cost is $134,818,308. 

Peter C. Hains, 

Colonel , U. 8. Corps of Engineers , Member . 


S. Doc. 264, 59-1- 4 













C HAP TER VII. 

EARTHQUAKES, VOLCANOES, CLIMATE, 

HEALTH. 


Earthquakes. 


So much has been written upon the liability of 
an isthmian canal to injury or destruction by earth¬ 
quakes that a brief discussion of the subject seems desirable. 

... . „ , The cause of earthquakes is not well understood, 

but amid the obscurity surrounding the subject 
there are a few salient facts which seem to be generally accepted. 

The first is that the geographical distribution of volcanoes corre¬ 
sponds with the areas most subject to earthquakes. One of the most 
celebrated and destructive earthquakes known to history—that of 

Lisbon in 1755 —occurred far from any volcano; 
subject to earthquakes? 0 ^ and so with that of New Madrid, Mo., in 1812, 

and that of Charleston, S. C., in 1886; but the 
general statement is correct, that they are more frequent in volcanic 
countries than elsewhere, though there is probably" no part of the 
earth’s surface which is entirely exempt from these disturbances. It 
does not follow that volcanoes and earthquakes bear to each other the 
relation of cause and effect, but it is highly probable that they repre¬ 
sent different manifestations of the same subterranean forces. a 

_ . „. The ’doctrine that volcanoes are safety valves 

which diminish the violence ot earthquakes in their 
vicinity is accepted by such writers as Baron von Humboldt, Sir Charles 
Lyell, Prof. Charles Daubeny, and J. Le Conte. b 

In general terms, then, the region of volcanoes is the region of 
earthquakes, but the immediate vicinity of the volcanoes is not neces¬ 
sarily the most dangerous part of the region. 

The location of the principal volcanoes in the 
caJii'c region t . 1,,nus ,n >o1 ’ part of the world where lies the isthmus is shown 

on plate 70. From a glance at this map it is evi¬ 
dent that the entire isthmus between North and South America is a 
volcanic region. Humboldt thus speaks of it: “The grandest example 
of a continental volcanic ‘chain’ is offered by the great rampart of 
the Andes extending from the southern part of Chile to the northwest 
coast of America.” 0 No portion of it is exempt from earthquakes. 


a 4 ‘Earthquakes,” by John Milne. D. Appleton & Co., N. Y., 1899. 
b Humboldt’s “Cosmos,” Sabine’s translation, eighth edition, Vol. I, p. 202; 
“Principles of Geology,” by Sir Charles Lyell, first American edition, Vol. I, p. 32; 
“Volcanoes,” by Charles Daubeny, second edition, p. 691; “Elements of Geology,” 
by J. Le Conte, fourth edition, p. 105. 
c Cosmos, Vol. I, p. 228. 


51 






52 


INTEROCEANIC CANAL, 


The record of those which have occurred is meager, being as a rule 
confined to those severe enough to inflict damage upon buildings or 
otherwise attract general attention. The most complete catalogue to 

which the Commission has had access is that pre- 
iiecords available. pared by Mr. F. de Montessus de Ball ore, a pub¬ 

lished in 1888. It covers the entire period from the time of the Spanish 
conquest to the year 1886. No very important earthquake has occurred 
upon either the Nicaragua or Panama lines since the latter date. 

The record for points upon the line of the Nicaragua Canal shows 14 
earthquakes. Two of these were felt at Grey Town, which has been 
supposed by some writers to be exempt. The only one which is 
reported to have caused serious injury was that of 1844—Rivas was 

almost destroyed, and great damage was done at 
* ua Grey Town. Rivas is 4 miles from the canal line, 
and is the ordy town of consequence in that part 
of Nicaragua. It has had a continuous existence since a period ante¬ 
dating the conquest, when it was known as Nicarao. It was subse¬ 
quently known as Nicaragua. 

For Panama the records show 28 earthquakes. Of these, 12 occurred 
in the three years 1882, 1883, and 1884, which illustrates the incom¬ 
pleteness of the record as a whole. The only one that could be called 
destructive was that of 1621, which destroyed nearly all the houses m 

Panama. The next most severe was that of Sep- 
^Earthquakes on Panama tember 7 ^ 1882. During this earthquake a part of 

the front of the cathedral in Panama was thrown 


Earthquakes on Nicarag 
line. 


down and the headquarters building of the canal company was cracked; 
the railroad had its track and roadbed in places thrown out of line, 
and the masonry of three or four bridges and culverts was damaged; 
at Las Cruces the church was thrown down; at Colon some lives were 
lost and crevasses were opened, and the Jamaica telegraph cable was 
broken 

It is evident that this list is not complete enough to justify a com¬ 
parison betw r een the Nicaragua and Panama routes as to either the 

number of earthquakes or their severity. They 
two°iin*! rence between the are on precisely the same footing historically as 

they are geographically. In neither case is there 
recorded any great disasters such as have occurred in neighboring 
countries. The earthquake of Caracas to the eastward in 1812, and 
that of Jamaica to the northward in 1692, are well known as among 
the most destructive in history. To the northwestward the town of 
San Salvador has been ruined ten times and that of Guatemala seven 
times. To the southward, the earthquake of Riobamba, in the prov¬ 
ince of Quito, in 1779, was one of the most terrible phenomena in the 
history of the globe. b With the exception of the injury to Panama 
in 1621 and to Rivas in 1844, the worst that has ever happened at the 
Isthmus upon either line was to throw down or crack a few walls; and 
even in those cases it is to be remembered that comparatively few of 
the houses were substantially built. 

The internal disturbance which results in an earthquake is trans- 


a Tremblements de Terre et Eruptions. Voicaniques au Centre-Amerique, by F. 
de Montessus de Ballore, p. 61. Societe des Sciences Naturelles de Saone-et-Loire, 
Dijon, 1888. 
b Cosmos, vol. 1, p. 194. 




INTEROCEANIG CANAL. 


53 


Mechanical 

earthquakes. 


action of 


Power of canal works to 
resist. 


mitted to any given point of the earth’s surface in the form of an 
elastic wave of compression, and its effects may be of infinite variety, 
depending upon the varying elasticity of the different media through 

which it passes, and their shape, as well as the 
strength and distance of the original impulse. 
The resulting motion may be vertical,‘horizontal, 
or oblique, and a circular or twisting effect may be produced if the 
direction of the force be not in a vertical plane passing through the 
center of gravity of the object acted upon. Twisting motion would 
also be produced by two waves crossing each other. The ground may 
be elevated or depressed, and fissures may be opened, these effects 
being sometimes temporary and sometimes permanent. The effect of 
the undulations of the earth’s surface upon any structure increases 
with the height of the structure above the ground. A force which 
would leave the foundation intact might throw down a high wall. 

The works of the canal- will nearly all of them be underground. 
Even the dams are low compared with the general surface of the 
country and with their broad and massive foundations may be said to 

form part of the ground itself as they are intended 
to do. The locks will all be founded upon rock. 
It does not seem probable that works of this kind 
are in any serious danger of destruction by earthquakes in a country 
where lofty churches of masonry have escaped with a few minor 
injuries. 

When an earthquake originates beneath the sea, one of its attendant 
phenomena is often a tidal wave, and this is sometimes of enormous 

height and destructive character. At Lisbon the 
Tidal wave. se a rose £ 0 a height of 50 feet above its ordinary 

level. a With a given force of impulse, the dimensions of such a wave 
must bear some relation to the depth and area of the water disturbed. 
A lake like that of Nicaragua is insignificant compared with the ocean. 
It is not probable that a tidal wave of great proportions could be gen¬ 
erated therein. The probability is still less for Lake Bohio. 

It is possible and even probable that the more accurately fitting 
portions of the canal, such as the lock gates, may at times be distorted 

by earthquakes, and some inconvenience may result 
injury to be expected. therefrom. That contingency may be classed with 

the accidental collision of ships with the gates, and is to be provided 
for in the same wa} r , by duplicate gates. 

It is possible also .that a fissure might open which would drain the 
canal, and if it remained open, might destroy it. This possibility 

should not be erected by the fancy into a threaten- 
i )a,,ger from a Ussure * i n g> danger. If a timorous imagination is to be the 
guide, no great work can be undertaken anywhere. This risk may be 
classed'with that of a great conflagration in a city like that of Chicago 
in 1871, or Boston in 1872. 

It is the opinion of the Commission that such danger as exists from 
earthquakes is essentially the same for both the Nicaragua and Panama 
routes, and that in neither case is it sufficient to prevent the construc¬ 
tion of the canal. 

The climate of the isthmian canal regions is 
( llmate * generally damp and enervating. The temperature 

is not extreme, rarely rising as high as 95° or falling below 70°, but 


11 Keith Johnston’s Physical Atlas, p. 40. 





54 


INTEKOCEANIC CANAL. 


the excessive humidity greatly restricts the capacity for physical exer¬ 
tion. The lowlands near the coast have long been known as insalu¬ 
brious, and the seaports are subject to fevers. 

,Iealth ‘ Perhaps the greatest difficulty to be encountered 

in the construction of the canal will be the procurement of an adequate 
force of laborers and the preservation of their health and efficiency. 

In this respect the Panama route has a lugubrious histoiy from 
which the Nicaragua route is free. The notorious mortality which 
attended the construction of the Panama Railroad and later the opera¬ 
tions of the Panama Canal Company has taught a 
Ianama lesson which will not soon be foi gotten for that 
route. Among the white emploj^ees of this Com¬ 
mission sent to Nicaragua there were fewer cases of sickness than 
there would probably have been among the same number of men 
employed in some parts of the United States. Among those sent to 
Panama the proportion of sick was greater. On the Nicaragua line 
during the operations of the Maritime Canal Company the health of 
the force was reported to be good. These operations, however, were 
of a preliminary character, employing but a limited number of men. 
It is probable that when ten or twenty thousand men are assembled 
and the rank soil is being turned up over a widely developed line of 
works the experience will be different. 

There are some slight differences of climate. In Nicaragua the 
trade winds are more regular than at Panama, tempering the heat and 
removing miasma more effectively; but, on the other hand, the rainfall 
is greater at Nicaragua, at least for the east side, and the resulting 
humidity is greater. Both are covered with the rank vegetation pecul¬ 
iar to the Tropics, and swamps abound in both. The lessons taught 
at Panama should be heeded for Nicaragua also. 

It is stated by Mr. Bunau-Varilla, at one time 
Lessons from Panama. chief engineer of the old Panama Canal Company, 

that out of one hundred individuals sent to the 
Isthmus not more then twenty, as an average, could remain there, and 
even these lost a part of their value. The negro alone could perform 
manual labor; the white man must supervise and direct. After costly 
and fatal experiments with other races the company ceased sending to 
the Isthmus as laborers any but native Colombians and negroes from 
the British Antilles, particularly Jamaica. The Panama Railroad 
Company grants to its white employees from the United States two 
months’ leave of absence each year, with transportation to their homes. 

Careful selection, including physical examination, of persons sent 
to the Isthmus, a well-organized hospital service, an efficient sanitary 

supervision of camps and barracks, a rigid quar- 
yation ofSth^ preser ' antine service, a liberal water supply and sewerage 

system, with the authority and the police force 
necessary to enforce the rules, and regular leaves of absence to white 
employees, are among the requirements for a successful prosecution 
of the work, and will probably be found necessary at either place. 


EXHIBIT C. 


A GENERAL DESCRIPTION OF THE VOLCANIC PHENOMENA FOUND 
IN THAT PORTION OF CENTRAL AMERICA TRAVERSED BY THE 
NICARAGUA CANAL.—THE POSSIBLE EFFECTS OF EARTHQUAKE 
SHOCKS ON THE STRUCTURES OF THE CANAL. 

[By Maj. C. E. Dutton, United States Army.] 

San Antonio Arsenal, 

San Antonio , Tex ., June 22, 1891. 
The President Nicaragua Canal Construction Company. 

My Dear Sir: I have your letter of 13th instant, in which you invite 
me to give a general description of the volcanic phenomena found in 
that portion of Central America traversed by the Nicaragua Canal, 
and to express any conclusions which I may have reached concerning 
the effects of possible earthquake disturbances upon the proposed 
structures of the canal. 

In reply, I would say that the portion of the canal between Lake 
Nicaragua and the Caribbean, apart from the San Juan River, traverses 
a country in which the rocks of the surface are mainly volcanic, but 
belong to a past geological age. No recent volcanoes or lavas are 
known to exist anywhere in the vicinity. Volcanic action has been 
wholly extinct there during the present geological age, and the surface 
lavas have been decomposed into a red clay, containing occasionally 
rounded bowlders of the original rock as the last remnants. Under¬ 
neath these red clays other lavas are found, some of them in a good 
state of preservation, others showing a partial decomposition. Inter- 
stratified with them are beds of volcanic ashes, to which your surveyors 
have given the name of slate and telpetate. 

The active volcanoes which are nearest to this portion of the canal 
are situated in Costa Rica. There are two chains of volcanoes in Costa 
Rica which exhibit signs of unrest and which may be regarded in a 
certain sense active, though the activit} 7 of some of them is nothing 
more than a little steam at the summits or from lateral vents. Much 
the greater number of peaks in these two chains have given no sign 
during the present century, and in most cases have been silent ever 
since the discovery of the country. There are, however, four or five 
of them which must be regarded as active, for they have within a century 
broken out in strong eruption and still maintain a condition of unrest. 

Of the two chains, the one nearest to the San Juan River is situated 
15 to 18 miles north of San Jose, the capital of the country, and include 
three volcanoes which may be regarded as active. Of these, the one 
nearest the San Juan is named Poas. It is 40 miles due south of the 
junction of the Rio San Carlos with the San Juan, and about 58 miles 
from the proposed location of the eastern locks. 


55 


56 


INTEROCEANIC CANAL. 


About 30 miles southeast of Poas is Irazu, the most active and forci¬ 
ble of all the Costa Rican volcanoes. It is about 58 miles from the 
junction of the San Carlos and a little more, say, 62 or 63 miles, from 
the eastern locks. About 6 miles east of Irazu, and substantially the 
same distance from the canal, is Turialla, also an active vent. 

The other volcanic chain is much longer. It lies near the Pacific 
coast, being only 12 to 15 miles distant from Puntarenas. It extends in 
a northwesterly direction as far as the Volcano Orosi, which is 38 miles 
southeast of the town of Rivas. It contains but one or two cones 
which may be regarded as active, though there are in all four or five 
which have at times disclosed some traces of volcanic action, but hardly 
enough to warrant us in calling them active. The Volcano Orosi, which 
is the northwesternmost of the chain and much nearer than any other 
to the canal, is not positively known to be in active vent; certainly it 
has given no sign within the memory of men now living in its vicinity. 
Nor does it have the appearance of an active cone. I was within 8 
miles of it on the northern side, whence it seemed to be an old cone in 
an advanced stage of degradation by weathering, and no traces of 
recent action were visible. I have been unable to find any record of 
an eruption from it. Yet it is reputed in the works of several writers 
to be active, though no dates or incidents of such an occurrence are 
given, so far as I have been able to learn. 

Nicaragua contains a single chain of volcanos parallel to the Pacific 
coast and generally about 20 miles from it. The southeastern most 
cones of this chain are the twin peaks Madera and Ometepe in Lake 
Nicaragua. They are about 15 and 11 miles, respectively, from the 
shore of the lake, and opposite the point at which the canal will leave 
it leading to the Pacific. Madera is apparently extinct, but Ometepe 
is active, having been in eruption in 1883. The proximity of these 
two cones to the canal makes them objects of special interest, for they 
are much nearer to it than any others. The next volcano of this chain 
is Mombacho, at the foot of which the large town Granada is situated. 
While there has been no eruption from it during the history of Nica¬ 
ragua, there are some lava streams emanating from it which bear the 
look of recency, and can not be more than a very few centuries old. 
It is also one of the principal sources of earthquakes and tremors. Its 
distance from the canal locks near Brito is, I believe, a little over 40 
miles. 

About a century ago a considerable eruption occurred near Masaya, 
some 16 or 18 miles beyond Granada. From the meager accounts pre¬ 
served, it would seem to have been attended with very little violence, 
though a very considerable body of lava was ejected and overflowed a 
large tract of country. This quiet form of eruption is sometimes seen 
elsewhere among basaltic outbreaks, and is especially characteristic 
of the vast lava floods of Mauna Loa and Kilauea in the island of 
Hawaii. There is no mountain or even large cinder cone to make the 
orifice of the Masaya eruption, which was situated in a comparatively 
low country. 

There is a group of volcanic cones on the southwest shore of Lake 
Managua, near the city of Managua, but they appear to be extinct. 
No other active volcano exists in this chain until Moinotombo, at the 
extreme western bay of Lake Managua, is reached. It is a large cone, 
and is always steaming at the summit, and gives evidence of a dormant 
activity in many ways. It is reputed to have erupted twice during the 








INTEROCEANIC CANAL. 


57 


present century, the last time only a few years ago. Twenty miles 
northwest of it and north of Leon is the volcano Santa Clara, which is 
also steaming, but as these two are more than 100 miles distant from 
the canal they may be regarded as outside the limits of discussion. 

In only one instance has any eruption in Central America been of the 
extremely violent class. The exception was the outbreak of Coseguina, 
on the Bay of Fonseca,, in 1835, which was one of the most forcible of 
the present century. Otherwise the eruptions have been of small or 
moderate energy, causing no serious and widely spread disasters. The 
ejections are largely in the form of scoria and ashes, though lava 
streams sometimes liow. 

As regards earthquakes, it is well known that they are comparatively 
frequent, especially in Costa Itica and Nicaragua, and a few have been 
destructive in very restricted localities. It is no doubt a matter of 
great interest to the canal company; for the question at once arises 
whether there is not danger of serious damage from this cause to the 
works of construction, and of the still more serious damage of long 
suspensions of traffic. In order to reach some estimate of the magni¬ 
tude of this danger, it may be well to state, as briefly as possible, some 
general considerations which must serve for a logical basis of any 
estimate: 

(1) The forecast of earthquakes contemplates probabilities only and 
not certainties. That one will happen in a particular region in a speci¬ 
fied number of years is a probability which is great or small according 
to the nature of the locality and its extent. We may view such proba¬ 
bilities as having the nature of risk analogous to those of fire and 
shipwreck, with the following difference: Fires and shipwrecks are of 
such frequent occurrence, and have been so thoroughly investigated by 
insurance companies, that their probabilities under widely varying cir¬ 
cumstances can be estimated with great precision, and the commercial 
value of the risk accurately determined. Earthquake risks have never 
been so investigated, and it is therefore impossible to assign specific 
numerical values to them. Nevertheless, it is sometimes practicable to 
show that the risk is so small that it can be left out of consideration 
with prudence, though we may not be able to assign its precise value. 

(2) In attempting to forecast the future probabilities of earthquakes, 
we must assume that the future will be like the past, precisely as is 
done in insurance probabilities. We must assume that w r here they 
have been frequent and violent they will continue to be so, and that 
countries seldom visited by them in the past will be as seldom visited 
in the future. There is no other possible basis of reasoning. 

(3) Earthquakes originate at very different depths in the earth, rarely, 
perhaps never, exceeding 12 miles, and generally not exceeding 3 or 4 
miles. We know almost nothing of the ultimate nature of the forces 
or causes which generate them; but we know considerable about the 
manner in which they are propagated after the} r have been started, and 
concerning their subsequent action and effects. Whatever may be the 
causes, we must assume that the subterranean track or seat in which 
they originate occupies some space of very limited extent and contains 
some point which may be regarded as its center—commonly called the 
centrum. From the seat of origin the impulses are propagated as elastic 
waves in every direction, in a manner having much in common with 
waves of sound in the air. 

(d) The intensity or violence of these waves diminishes like that of 


58 


INTEBOCEANIC CANAL. 


the air, at as rapid a rate as they are propagated. At any given spot 
the intensity is inversely proportional to the square of the distance 
from the centrum. 

(5) In all destructive earthquakes, the extent of country in which 
they are destructive is but a small fraction of the total area throughout 
which the tremors are perceptible. Ordinarily it is not far from the 
four-hundredth part of the area perceptibty shaken. The area in which 
the shocks may cause damage varying from slight to serious (but not 
demolition or what are usually considered destructive effects) is com¬ 
monly about four to eight times as large as the destructive area, or 
from the tiftieth to the one-hundredth part of the area of perceptible 
vibration. Those ratios are only roughly approximate, and they are 
subject to some qualification, ordinaril}^ not large, dependent on the 
depth of the centrum. They are of importance as showing the com¬ 
paratively narrow localization of destructive and even damaging 
effects. Still, the destructive areas may in some cases be absolutely 
considerable, being proportional to the total energy of the shock at the 
centrum. The' destructive area of the Charleston quake had a radius 
of not far from 10 miles, but its tremors were perceptible at a distance 
of 700 to 1,000 miles. Its great extent, as well as the distances at which 
its tremors were felt, cause it to rank among the most powerful shakes 
of the present century. Its intensity at the surface, however, while 
formidable, was not so excessive as has been experienced in some other 
memorable earthquakes. This was because its depth was extreme, 
being in all probability one of the most deeply seated of which we 
have sufficient knowledge to form an opinion. In striking contrast 
was the Casamicciola earthquake, on the island of Ischia, in the Bay of 
Naples, in 1884. Here the destructive area had a radius of less than 2 
miles, but within that area the violence was superlative and the havoc 
great. At Naples, 25 or 30 miles away, the shock was only a faint 
tremor. The depth of the Charleston quake is computed at about 12 
miles, with a very moderate probable error. The Casamicciola quake 
had its origin at a depth, probably, of less than half a mile. Immedi¬ 
ately over the centrum its intensity was apparently quite equal to that 
in the central area of the Charleston, but the total energy of the shocks 
was hardly one seven-hundredth part as great. These two extreme 
instances may illustrate the varying effects of total energy and depth 
upon surface intensity. The comparison is analogous to one on a 
smaller scale between the explosion of 100 pounds of dynamite at a 
depth of 100 feet and of 30 tons at a depth of half a mile. The effects 
at the “ epicentrum ” (point on the surface vertically over the centrum) 
would not differ much, but the larger and deeper charge would affect 
a vastly greater area and would be felt at a much greater distance. 

The foregoing will suffice for our purpose, and it is needless to enter 
into a general discussion of the principles involved in earthquakes. It 
only remains to put those already set forth into relation with the facts 
presented in Nicaragua and Costa Rica. 

In both of these countries the principal earthquakes, so far as we 
know them, and perhaps we may say all the forcible ones, have had 
their centra in close proximity to the volcanoes or underneath them, and 
are incidents apparently of the volcanic activity. There is no evidence 
nor any suggestion, so far as I can ascertain, that any of them have 
originated at a considerable distance from the volcanoes. The country 
on either side of the volcanic chains has not been visited by any earth- 


INTER0CEAN1C CANAL. 


59 


quake shock except such as have been transmitted through the rock 
from the centra within the volcanic areas. 

^ Earthquakes are frequent in the vicinity of San Jose, the capital of 
Costa Rica, and of the other towns surrounding it upon the high, fertile, 
and populous plateau of this country. A very few of them have been 
more or less destructive. By far the most energetic one occurred in 
1841, completely destroying the large town of Cartago, situated at the 
base of Irazu, and killing many people. The intensity or violence of 
this quake, in close proximity to the centrum, appears to have been 
very great. But the indications, from the imperfect accounts we have 
of them, are to the effect that the intensity declined with increasing 
distance at a very rapid rate; for at San Jose, only 13 miles distant 
from Cartago, the intensity hardly reached the destructive stage, and 
the injuries to the buildings were seldom great. In towns somewhat 
more remote the shocks caused great terror, but no serious damages, 
while at a distance of 40 miles or more they appeared to have been 
harmless. These accounts are very characteristic of the Casamicciola 
type of earthquake, involving a shallow centrum, a rather small “epi- 
central tract 1 ' with high intensity (because of the shallowness of the 
origin), and a rapid decline of intensity with increasing distance, because 
of a relatively small or moderate amount of total energy. The accounts 
of other earthquakes in Costa Rica which have occasioned serious 
damage or destruction are very meager. But their general tenor is 
indicative of similar characteristics, but of less total energy. In gen¬ 
eral, it may be said that the earthquakes of that country appear to be 
very local in their destructive effects, and the shocks become harmless 
quivers or tremors within 20 or 30 miles of their origin. 

The portion of the canal between Ochoa and the Caribbean is, in my 
opinion, too remote from the localities in which the Costa Rican earth¬ 
quakes originate to be liable to any serious injury from them. At long- 
intervals of time, averaging perhaps from five to ten years, some excep¬ 
tionally powerful shock may transmit waves as far as the canal with 
sufficient intensity to produce marked vibrations and tremors; but that 
they will have force enough to materially injure the structure of the 
canal is, in my judgment, too improbable to call for any special pre¬ 
cautions against them. Very light and barely noticeable tremors will 
be much more common. If it could be shown that strong shocks have 
had their origin near the line of the canal, the danger would be much 
more pronounced. But I am not aware that there is any indication 
whatsoever of such an occurrence. It is true that light tremors have 
been noticed in Grey town, but they are in all probability the vanish¬ 
ing waves of forcible shocks originating far to the southward. There 
is no reason to suppose that the country through which this portion of 
the canal extends is an earthquake country. The risk of damage from 
that cause I regard as immaterially small. 

With respect to the portion of the canal leading from Lake Nicaragua 
to the Pacific there seems to be a somewhat larger risk, but not large 
enough to cause any serious apprehension. The volcano Ometepe in 
the lake is only about 13 miles from the outlet of the canal, and about 
21 miles from the locks. Its eruption in 1883 was a somewhat forcible 
one, attended with strong tremors, which sufficed to produce some 
cracks in the houses and area walls in Rivas. a I saw several of these 
cracks, though they were not common and in no case endangered the 


u Rivas is about halfway between Ometepe and the locks. 






60 


INTEROCEANIC CANAL. 


structures. The canal locks, if they had been in existence at the time, 
would probably not have been injured, if built on rock foundations or 
upon very solid earth not liable to slip or settle under a series of such 
tremors. The tremors there were considerably lighter than at Rivas, 
and they would be much less susceptible of damage than the fragile 
walls of which Central American houses are built. A few cracks in a 
large town indicate a fairly definite degree of intensity, and give a far 
better measure of it than the terror and panic of the inhabitants. 

Although the eruption of Ometepe in 1883 was the first since the 
conquest, earthquakes have before emanated from it, and some of them 
have been as forcible as the one spoken of, but none, so far as can be 
ascertained, that were measurably more so. 

With regard to the possibility of earthquakes originating from 
Orosi, a we have not sufficient data to warrant any very definite opinion. 
It stands in a wilderness which has always been little inhabited except 
by Indians, and if any earthquakes have originated there the shocks 
were so enfeebled by the time they reached the settled portions that 
they were harmless. Nor would it be practicable for a people unob¬ 
servant in such matters to ascertain their source, or to collate from an 
uninhabited country the facts which would enable others to determine 
it. As this volcano is situated 40 miles from the canal locks, it would 
require much more decisive indications of seismic activity in its neigh¬ 
borhood than we now know of to justify any fears from it. To all 
appearance it is a long-extinct volcano, not likely to trouble the world 
again with any eruption or violent shakings. 

The Volcano Mombacho b is a center of decided earthquake activity. 
A very few years ago—the exact year I do not recall—the city of 
Granada, at its base, was severely shaken, many houses being damaged 
and a number of them wrecked. A large church nearly ready for the 
roof was badly shattered. A few lives were also lost. This shock was 
felt forcibly at Managua, about 30 miles distant, and though it caused 
much alarm and even panic there, it does not seem to have produced 
any serious damages. At Rivas, 0 which is about twice as far from 
Mombacho as Managua, it was harmless, though causing much alarm. 
It requires only a light and harmless shake, but one perceptible to 
everybody, to cause great fear and even panic. Other shocks, some of 
great force, have been known to emanate from Mombacho. The seismic 
center, however, is too remote from the canal to be a source of any 
apprehension. 

No shocks are known ever to have originated along the line of the 
canal from the lake to Brito, nor in any dangerous proximity to it, 
except those from Ometepe. This section of the canal does'not in 
realit} r lie within the volcanic axis or areas. The Nicaraguan chain, 
beginning with Madera and Ometepe, is a little to the north of it, and 
the western Costa Rican chain ends with Orosi. The nearness of 
Ometepe, d however, would be a source of danger were it not for the 
fact that the past behavior of the volcano has been for more than two 
centuries so moderately demonstrative as to give little cause of appre¬ 
hension of more vigorous action in the future. Unless future shocks 
from it should be much more powerful than in the past, they will not 


a In Costa Rica. 

b In Nicaragua, 35 miles north of the canal line. 
c Rivas is between Mombacho and the canal. 
d Ometepe is 22 miles distant, from the locks. 




INTEROCEANIC CANAL. 


61 


endanger the locks; and there is nothing else on this part of the line 
which an earthquake would be likely to injure. 

There is a tendency on the part of nearly all persons who have not 
made special study of the subject to entertain exaggerated ideas of the 
risks and dangers of what are termed earthquake countries. The ter¬ 
rors of the ‘ epicentral tract” in a great devastating series of shocks 
can not, indeed, be exaggerated. The error consists in assuming them 
to be frequent, widespread, and typical of the country. In truth, they 
are rare, even in the most afflicted region, and when they do come they 
are destructive within relatively narrow limits only, while the country 
at large is shaken only by harmless quivers. It is exceedingly rare for 
one generation living on any spot on earth to have seen two destroying 
earthquakes in the same locality. In many volcanic countries there are 
a few spots where such catastrophies repeat themselves, though usually 
after very long intervals of } T ears. These are known and can be shunned 
by the engineer and architect, if need be. Apart from these, all local¬ 
ities within an earthquake country sufficiently removed from the known 
centers or axis may be regarded as being in far less peril from earth¬ 
quakes than from sweeping destruction by an uncontrollable tire. 

Briefly, then, my opinion is that the risk of serious injury by earth¬ 
quakes to the constructions proposed for the Pacific section of the canal 
is so small that it ought to be neglected alike by the Maritime Canal 
Company, the Construction Company, and by contemplating investors; 
also, that the risks to the Atlantic section are still smaller than those 
to the Pacific section. 

You suggest that I submit “some observations upon the subjects of 
the effects upon engineering superstructures and substructures of those 
earth movements which in some instances have destroyed cities and 
population, changing topographical features of localities, and, on the 
other hand, movements which have destroyed in some instances 
massive works and have passed harmlessly others of seemingly frail 
construction.” 

Observations of the effects of great shocks upon buildings of many 
kinds are very abundant and have been carefully made and studied. 
It may be said in general that superstructures of stone or brick are far 
more liable to injury than substructures, excepting in those transcend¬ 
ent quakes which nothing, not even the earth mass itself, can withstand. 

In shocks which are less than superlative, though still destructive, 
foundations are seldom much injured, even when superstructures are 
extensively demolished. A superstructure is liable to cumulative vibra¬ 
tion, i. e., to oscillations of steadily increasing amplitude, while a sub¬ 
structure is not. Any ordinary walled structure is liable to have, either 
as a whole or in some of its parts, a definite vibratory period. If this 
period be the same as or a small but exact multiple of the period of a 
series of earthwaves the extent of vibration will rapidly increase and 
the liability to destruction is greatly multiplied. 

A substructure can have no greater amplitude of movement than the 
ground itself. Only in the most formidable earthquakes are foundations 
likely to suffer, except, perhaps, incidentally and secondarily from 
abnormal strains thrown upon them by the rocking of the superstruc¬ 
ture. The escape of fragile structures while strong ones are overthrown 
is not a mystery. They are not in harmony with the wave period, and 
therefore "not liable to cumulative vibration. 


62 


INTEROCEANIC CANAL. 


There is a mistaken impression prevailing among those who are 
unfamiliar with recent progress in seismic investigation, which it is 
important for engineers to be advised of. It is a common impression 
that earthquake motion has a definite direction in each case. There is 
no warrant for this in theory, and the seismograph wholly disproves it. 
There is no one direction of motion to a particle on the ground during 
an earthquake. The motion is in every direction. Perhaps I can best 
express it by sa} 7 ing that the ground squirms and wriggles. The path 
of an earth particle during a shake is like a long hair rolled up into a 
ball between the flattened palms of your hands, or like the path of a 
fly hovering under a chandelier. Still, it is usual for the components of 
all the motions to have some slight, and sometimes a very marked, pre¬ 
dominance in one direction. The vertical components are generally 
smaller, except in very close proximity to the epicentrum, where they 
may become very large. Away from the epicentrum the largest hori¬ 
zontal component will more frequently, but by no means always, be in 
a line connecting the place with the epicentrum, or nearly in that direc¬ 
tion. But the maximum vibration may be in any direction, being deter¬ 
mined probably by accidents of the ground. It would be illogical, 
therefore, to attempt to fortify against earthquakes b} 7 building struc¬ 
tures calculated to resist movements coming from any specific quarter, 
unless, indeed, it be decided to follow the example of the deacon in build¬ 
ing the ‘ 6 One Horse Shay.” The only precaution I know of which is of 
the slightest utility is to build on solid rock instead of subsoils, gravels, 
or any sort of unconsolidated strata. The amplitude of motion during 
a quake is less, and there is less liability to permanent displacement. 
But in the visitation of a first-class earthquake even this precaution 
would be useless. 

The structures most easily injured would undoubtedly be the locks. 
The masonry might be cracked by a powerful shock, but unless the 
ground beneath were permanently displaced or the walls moved bodily 
the damage could be repaired at small cost. The gates might be jammed 
or broken or slightly displaced also. But shocks of sufficient severity 
to produce any of these results are hardly to be anticipated. The dams, 
if built in the manner proposed, of loose rock with very long slopes (6 
or 8 to 1), would require shocks of extraordinary power, accompanied 
with considerable displacement of the ground beneath them, to damage 
them. As against earthquakes, they would be the safest that could 
possibly be built. 

Being already nothing but shattered fragments, it is not apparent 
what more an earthquake could do except to dislocate the earth beneath 
them. Such permanent distortions of the earth do not occur except in 
the most forcible convulsions, far more forcible than any that have ever 
been known to occur in Nicaragua. 

Very truly, yours, 


C. E. Dutton, 

Major, Ordnance Department , United States Army. 


EARTHQUAKES. 


RELATION OF THE CANAL ROUTE TO CENTERS OF VOLCANIC ACTIVITY. 

Most earthquakes for which a cause can be assigned with any degree 
of probability are produced either by an explosion at greater or less 
depth below the earth’s surface or by a dislocation of the earth’s crust 
producing a fault. The former class is confined chiefly to volcanic 
regions, and if the explosions are sufficiently long continued they 
eventual^ find a vent at the surface and produce an active volcanic 
eruption. Earthquakes produced by faulting are also to some extent 
characteristic of volcanic regions, but may occur remote from any 
scene of volcanic activity, especially in regions which are undergoing 
rapid elevation or depression. They are especially characteristic of 
regions in which the mountain-building forces are active. Earth¬ 
quakes of the latter class, due to dislocations of the strata, are perhaps 
no more liable to occur in the vicinity of the Nicaraguan Canal route 
than elsewhere, and hence they do not constitute a danger which is 
peculiar to this region more than to almost any other in which a ship 
canal might be constructed. Earthquakes of the first class, however, 
are assumed to constitute a menace to the permanence of the canal, 
inasmuch as the region is one of 'considerable volcanic activity. The 
question of the risk incurred from this source is certainly one which 
should be considered. 

In the foregoing description of the topography and geology of the 
region the distribution of modern volcanic activity was indicated. It 
was shown that, while the Nicaraguan depression is occupied to a con¬ 
siderable extent by volcanic rocks, these belong in large measure to a 
former geological period, and the activity to which they owe their origin 
has long since entirely ceased. It was shown, further, that the only 
manifestation of volcanic activity in recent times has been along two 
lines of vents which have given rise respectively to the Costa Rican 
and the Nicaraguan volcanic ranges. The former terminates to the 
northward in the peak of Orosi. This volcano appears at present to 
be entirely extinct, and there is no authentic record or tradition of its 
having been in eruption since the occupation of the country by the 
Spaniards. Dutton described it as to all appearances a long extinct 
volcano; an old cone in an advanced stage of degradation by weather¬ 
ing and showing no traces of recent action. Squire, a however, speaks 
of it as in a state of constant activity, but he does not describe it from 
personal observation, nor does he give the date of any authenticated 
eruption. 

a E. G. Squire, “The States of Central America,” New York, 1858, p. 361. 

63 






64 


INTEROCEANIC CANAL. 


Of the numerous volcanoes in the Costa Rican range to the south¬ 
east of Orosi only one has shown any activity within historic times. 
This is Irazu, near the center of the range, which was last in eruption 
in 1726. As described by Hill, “the entire crater occupies but a rela¬ 
tively small portion of the great mountain mass which it caps and is 
apparently a later parasitic summit growth upon a much older mass.” a 
It is evident that the eruption which gave rise to the present conical 
summit of Irazu is an expiring phase of the activity which produced 
the massive mountain range. 

The Nicaraguan range terminates to the southward in the twin peaks 
of Madera and Ometepe, occupying the island of Omoytepe. The inter¬ 
val between the northern terminus of the Costa Rican range and the 
southern terminus of the Nicaraguan range is about 30 miles, and 
between these points passes the sailing line of the canal in Lake 
Nicaragua. Madera may be regarded as extinct. There is no tradi¬ 
tion of its having shown activity, and its summit has been greatly 
modified by erosion, indicating that there have been no eruptions for 
a very considerable time. Ometepe is quiescent. It manifested a 
slight activity in 1883 when there was an eruption of lapilli with 
explosions of moderate violence. At present the only sign of activity 
consists in numerous fumeroles from which steam and sulphurous 
gases escape. While no eruption of Ometepe appears imminent, there 
is no certainty that its activity has entirely ceased, although the indi¬ 
cations are that it is on the wane. Mombacho has been extinct for a 
long time. Its last eruption was probably one of the explosive type 
and destroyed its conical summit. Masaya was in eruption in 1858, 
but the eruption was not accompanied by explosion, simply consisting 
of the welling up and overflow of fluid basaltic lava. Momotombo, at 
the northern end of Lake Managua, shows signs of moderate activity. 
It is not at present erupting solid material, but throws off great vol¬ 
umes of vapors, which form a black cloud over its summit. Steam and 
other vapors are escaping from several craters to the northward of 
Momotombo, but from none of them are any lavas or lapilli being.. 
extruded. 

It is thus seen that the present activity of the volcanic vents which 
form the Costa Rican and Nicaraguan ranges belongs almost entirely 
to the solfataric stage which characterizes the extinction of volcanic 
activity. Considering the great mass of material which has been 
extruded from these vents in comparatively recent geologic times, it 
is very clear that the activity in this region is on the wane; and while 
eruptions will doubtless occur in the future, it can be asserted with a 
fair degree of confidence that these will be less violent and occur at 
longer intervals than in the past. It is also clear that the greatest^ 
activity at present and hence the source of greatest danger in the" 
immediate future is not in the vents which terminate the volcanic 
ranges, but rather in the central portion of those ranges; that is, in 
central Costa Rica and in northern Nicaragua. The experience of 
many years proves that these regions which are the centers of greatest 
volcanic activity are also the centers from which emanate most of the 
earthquakes felt throughout the Nicaraguan depression. 

a The Geological History of the Isthmus of Panama and Portions of Costa Rica, bv 
Robert T. Hill, Bull. Mus. Comp. Zool., Vol. XXVIII, 1898, p. 230. 








INTEROCEANIC CANAL. 65 

CONSIDERATIONS AFFECTING EARTHQUAKE FORECASTS. 

rhe subject of earthquakes in this region and their bearing upon 
the problem of the canal have been studied by Maj. C. E. Dutton, 
than whom no one is better qualified to speak on this subject. His 
report accompanies the report of the Nicaragua Canal Board of 1895, 
and his discussion of some of the principles of earthquakes in general 
and their application to this particular region are quoted below. 

As regai’ds earthquakes, it is well known that they are comparatively frequent, 
especially in Costa Rica and Nicaragua, and a few have been destructive in very 
restricted localities. It is no doubt a matter of great interest to the canal company; 
for the question at once arises whether there is not danger of serious damage from 
this cause to the works of construction, and of the still more serious damage of long 
suspensions of traffic. In order to reach some estimates of the magnitude of this 
danger, it may be well to state, as briefly as possible, some general considerations 
which must serve for a logical basis of any estimate: 

(1) The forecast of earthquakes contemplates probabilities only and not certainties. 
That one will happen in a particular region in a specified number of years is a prob¬ 
ability which is great or small according to the nature of the locality and its extent. 
We may view such probabilities as having the nature of risk analogous to those of 
fire and shipwreck, with the following difference: Fires and shipwrecks are of such 
frequent occurrence, and have been so thoroughly investigated by insurance com¬ 
panies, that their probabilities under widely varying circumstances can be estimated 
with great precision, and the commercial value of the risk accurately determined. 
Earthquake risks have never been so investigated, and it is therefore impossible to 
assign specific numerical values to them. Nevertheless, it is sometimes practicable to 
show that the risk is so small that it can be left out of consideration with prudence, 
though we may not be able to assign its precise value. 

(2) In attempting to forecast the future probabilities of earthquakes, we must 
assume that the future will be like the past, precisely as is done in insurance prob¬ 
abilities. We must assume that where they have been frequent and violent they 
will continue to be so, and that countries seldom visited by them in the past will be 
as seldom visited in the future. There is no other possible basis of reasoning. 

(3) Earthquakes originate at very different depths in the earth, rarely, perhaps 
never, exceeding 12 miles, and generally not exceeding 3 or 4 miles. We know 
almost nothing of the ultimate nature of the forces or causes which generate them, 
but we know considerable about the manner in which they are propagated after 
they have been started, and concerning their subsequent action and effects. What¬ 
ever may be the causes, we must assume that the subterranean tract or seat in which 
they originate occupies some space of very limited extent and contains some point 
which may be regarded as its center—commonly called the centrum. From the seat 
of origin the impulses are propagated as elastic waves in every direction, in a man¬ 
ner having much in common with waves of sound in the air. 

(4) The intensity or violence of these waves diminishes like that of the air, at as 
rapid a rate as they are propagated. At any given spot the intensity is inversely 
proportional to the square of the distance from the centrum. 

(5) In all destructive earthquakes, the extent of the country in which they are 
destructive is but a small fraction of the total area throughout which the tremors are 
perceptible. Ordinarily it is not far from the four-hundredth part of the area percep¬ 
tibly shaken. The area in which the shocks may cause damage varying from slight 
to serious (but not demolition or what are usually considered destructive effects) is 
commonly about four to eight times as large as the destructive area, or from the 
fiftieth to the one-hundreth part of the area of perceptible vibration. Those ratios 
are only roughly approximate, and they are subject to some qualification, ordinarily 
not large, dependent on the depth of {he centrum. They are of importance as show¬ 
ing the comparatively narrow localization of destructive and even damaging effects. 
Still, the destructive*"areas may in some cases be absolutely considerable, being pro¬ 
portional to the total energy of the shock at the centrum. The destructive area of 
the Charleston quake had a radius of not far from 40 miles, but its tremors were per¬ 
ceptible at a distance of 700 to 1,000 miles. Its great extent, as well as the distance 
at which its tremors were felt, cause it to rank among the most powerful shakes of the 
present century. Its intensity at the surface, however, while formidable, was not 
so excessive as has been experienced in some other memorable earthquakes. This 
was because its depth was extreme, being in all probability one of the most deeply 


S. Doc. 264, 59-1-5 





G6 


INTEROCEANIC CANAL. 


seated of which we have sufficient knowledge to form an opinion. In striking con¬ 
trast was the Casamicciola earthquake, on the island of Ischia in the Bay of Naples, 
in 1884. Here the destructive area had a radius of less than 2 miles, but within that 
area the violence was superlative and the havoc great. At Naples, 25 or 30 miles 
away, the shock was only a faint tremor. The depth of the Charleston quake is 
computed at about 12 miles, with a very moderate probable error. The Casa¬ 
micciola quake had its origin at a depth, probably, of less than half a mile. 
Immediately over the centrum its intensity was apparently quite equal to that in the 
central area of the Charleston, but the total energy of the shocks was hardly one 
seven-hundreth part as great. These two extreme instances may illustrate the vary¬ 
ing effects of total energy and depth upon surface intensity. The comparison is 
analogous to one on a smaller scale between the explosion of 100 pounds of dynamite 
at a depth of 100 feet and 30 tons at a depth of half a mile. The effects at the “epi- 
eentrum” (point on the surface vertically over the centrum) would not differ much, 
but the larger and deeper charge would affect a vastly greater area, and would be 
felt at a much greater distance. 

There is a tendency on the part of all persons who have not made special study of 
the subject to entertain exaggerated ideas of the risks and dangers of what are termed 
earthquake countries. The terrors of the “epicentral tract” in a great devastating 
series of shocks can not, indeed, be exaggerated. The error consists in assuming 
them to be frequent, widespread, and typical of the country. In truth, they are 
rare, even in the most afflicted region, and when they do come they are destructive 
within relatively narrow limits only, while the country at large is shaken only by 
harmless quivers. It is exceedingly rare for one generation living on any spot on 
earth to have seen two destroying earthquakes in the same locality. In many vol¬ 
canic countries there are a few spots where such catastrophes repeat themselves, 
though usually after very long intervals of years. These are known and can be 
shunned by the engineer and architect, if need be. Apart from these, all localities 
within an earthquake country sufficiently removed from the known centers or axis 
maybe regarded as being in far less peril from earthquakes than from sweeping 
destruction by an uncontrollable fire. 

Briefly, then, my opinion is that the risk of serious injury by earthquakes to the 
constructions proposed for the Pacific section of the canal is so small that it ought 
to be neglected; * * * also, that the risks to the Atlantic section are still smaller 
than those to the Pacific section. 


SEISMIC RECORDS IN THE CANAL REGION. 

On the 29th of April, 1898, there occurred an earthquake which 
was perceptible throughout the greater part of the Nicaraguan depres¬ 
sion, and which was moderately destructive in the towns of Leon, 
Managua, and Chinandaga. A commission consisting of Dr. Carlos 
Sapper and Dr. Bruno Miersch was appointed by the Government of 
Nicaragua to investigate the cause of this earthquake. This commis¬ 
sion visited the region affected and made the ascent of numerous vol¬ 
canic peaks in the vicinity of its greatest violence. They found no 
signs of imminent eruption in any of the craters visited, and reached 
the conclusion that the earthquake was due, not to a volcanic explo¬ 
sion beneath one of the numerous craters of the region, but to a dis¬ 
location of the strata. It is probable, as has been indicated in a 
preceding part of this report, that this region to the north of Lake 
Nicaragua has been affected by faults in comparatively recent times, 
and the present earthquake may be* due to a further displacement 
along one of these old lines of fracture or to the inauguration of a 
new fracture. The absence of any signs of increased activity in the 
volcanic craters, however, is scarcely conclusive evidence that the 
earthquake was not due to a deep-seated explosion intimately con¬ 
nected with the causes of the vulcanism. It is the deep-seated "explo¬ 
sions, those not relieved by an eruption at the surface, which probably 
cause the most destructive earthquakes. When a vent is formed with 
an open passage from the seat of the explosion to the surface, the 


INTEROCEANIC CANAL. 


67 


violence of the effects is diminished, or rather it is manifested in an 
eruption of lapilli and lava rather than in earthquake waves trans¬ 
mitted through the crust to the surface. 

Leon was visited by the writer shortly after the earthquake of 
April. 1898. The effects observed in that city were chiefly the forma¬ 
tion of cracks in the walls and the partial destruction of buildings 
constructed of adobe. This material has very slight coherence and is 
poorly.adapted to resist the strains produced b} T earthquake vibra¬ 
tions. No solidly built wooden or stone buildings suffered greater 
damage than the formation of a few cracks over the doors and win¬ 
dows. The cathedral of Leon suffered no damage except the displace¬ 
ment of a large globe which rested on a slender support on the 
ornamental facade of the building. It was concluded that if such a 
structure as a canal lock built on a suitable foundation had occupied 
the epicentral tract of the Leon-Chinandaga earthquake it would have 
suffered no material damage, almost certainly not enough to interfere 
with its continuous use. The risk at points 200 miles distant from 
the epicentrum, that is, at the nearest point on the canal route, would 
have been entirely negligible. 

The only source of possible danger from earthquakes to the eastern 
division of the canal lies in the Costa Rican volcanoes. Occasional 
earthquakes are experienced in central Costa Rica, the most violent 
since the occupation of the country b} 7 the Spaniards having been the 
one which destroyed the town of Cartego in 1841. This emanated 
from the neighboring volcano of Irazu and was of the shallow type 
with a small epicentral tract. It was only slightly destructive at San 
Jose, about 13 miles farther from the source than Cartego. The 
much greater distance of the canal from this volcano renders the 
probability of an earthquake from that source extending its destruc¬ 
tive area so far as the canal structures extreiiiely small. 

Two sources of danger to the western division of the canal are 
present, in Orosi to the south and in Ometepe to the northeast. As 
stated above, there is some doubt as to the condition of Orosi. The 
probabilit} 7 , however, is that this volcano is extinct. There are no 
records or traditions of destructive earthquakes having affected this 
region, although from the absence of large towns it is doubtful if the 
absence of records should be considered as conclusive evidence that 
such earthquakes have not occurred. The distance of this volcano 
from the nearest canal structures which would be liable to injury is so 
great that unless the disturbances were of exceptional violence the 
only effect at the canal line would be harmless earth tremors. The 
extent of the danger from Ometepe can be somewhat more accurately 
gauged. This volcano was regarded as extinct up to the date of its 
eruption in 1883. It was clothed with vegetation entirely to the sum¬ 
mit. Some earthquakes had emanated from Ometepe before the erup¬ 
tion. Squire speaks of the town of Rivas as having suffered much 
from earthquakes previous to 1850, but gives no details of their fre¬ 
quency or violence. The one which accompanied the eruption of 
Ometepe in 1883 was only very slightly destructive even at Rivas, 
and at the line of the canal its destructive violence had doubtless 
entirely disappeared. Even with the intensity manifested at Rivas it 
would in all probability have been entirety harmless to such a struc¬ 
ture as a canal lock. It is not probable that those which preceded 
that of 1883 were much more destructive or some record of them 


68 


INTEROCEANIC CANAL. 


would have been preserved. Indeed, the excellent state of preserva¬ 
tion in which the ancient churches of Rivas and San Jorge are found 
is conclusive evidence that the region has not been visited by earth 
quakes of destructive violence for more than a century. 

A consideration of the present activity in these two volcanoes, 
therefore, and of the available records of earthquakes in this region 
would seem to remove all apprehension concerning the probability of 
damage to canal structures by earthquakes emanating from them. If 
the danger from these sources, which are comparatively near, be con¬ 
sidered so small that it may be disregarded, that from the more dis¬ 
tant centers of volcanic activity, both to the north and the south, may 
be dismissed as altogether too small to merit consideration. Even if 
there should originate at the present centers of greatest activity an 
earthquake with as great violence as that which has characterized some 
that have wrought the most destructive effects in Peru and San Salvador, 
it is probable that the earth waves would there be so far dissipated 
before reaching the line of the canal that they would be comparatively 
harmless. It therefore appears to the writer that the opinion above 
quoted from Major Dutton is entirely correct, namely, that the risk of 
serious injury by earthquakes to the constructions proposed is so 
small that it ought to be neglected. 


[Senate Document No. 393, Fifty-seventh Congress, first session.] 

LETTER FROM THE SECRETARY OF STATE, TRANSMITTING COPY OF A 
DISPATCH FROM THE FORMER VICE-CONSUL OF THE UNITED STATES 
AT PANAMA CONTAINING DATA IN REGARD TO THE EARTHQUAKE 
THERE IN 1882. 

Department of State, 
Washington , June 5 , 1902. 

Sir: I have the honor to acknowledge the receipt of your letters of 
May 31 and June 2, 1902, requesting copies of certain records of the 
Department in regard to earthquakes and riots in Panama, Colombia. 

In reply I inclose herewith a copy of a dispatch from the former 
vice-consul of the United States at Panama, transmitting newspaper 
clippings in regard to the earthquake there in 1882. 

The records on the subject of the riot in Panama in 1856 will make 
about 1,000 pages of typewriting, and with our available force it will 
be impossible to furnish copies of these records within a month. 

Referring to your letter of the 3d instant, I have to say that the 
Department’s records contain nothing at all with reference to a propo¬ 
sition by Colombian authorities respecting annexation. 

I have the honor to be, sir, } T our obedient servant, 

John Hay. 

Hon. John T. Morgan, 

. United States Senate. 


United States Consulate, 
Panama , September ij, 1882. 

Sir: By this mail I forward to the Department a copy of the weekly 
edition of the Star and Herald of to-day’s date, which contains a full 




INTEROCEANIC CANAL. 


69 


and graphic account of the severe earthquake which visited this city 
on the 7th instant at 3.25 o’clock a., m. 

I am, sir, your obedient servant, 

Robert W. Turpin, 

Vice- Consul. 

Hon. William Hunter, 

Second Assistant Secretary of State , 

Washington , I). C. 


[Star and Herald, September 14, 1882.] 

SEVERE EARTHQUAKE ON THE ISTHMUS—MUCH DAMAGE DONE. 

During the past week the Isthmus has been visited by several earthquakes which 
have done damage, but which fortunately have only caused two deaths. The follow¬ 
ing, copied from the daily Star and Herald, describes the events as they occurred 
from day to day: 

[Daily Star and Herald, September 8.] 

On Thursday, 7th instant, at 3.20 in the morning, the inhabitants of Panama were 
aroused from their beds by one of the longest and most severe earthquake shocks 
■which has ever been experienced in this city. It was preceded by a hollow, rum¬ 
bling noise which aroused and alarmed many persons. The motion was wave like, 
and proceeded almost directly from north to south. The first and most severe shock 
must have lasted at least 30 seconds. Commencing with a moderate movement, 
it deepened in intensity, and toward the finish was so violent in strength that had it 
lasted 10 seconds longer it is probable that at this moment there would not be a 
house standing in Panama: The shock had hardly terminated when the streets 
were filled with people, many of whom sought the outskirts of the town in order to 
avoid danger from the fall of edifices. A second and milder shock occurred about 
half an hour after the first one. 

It is almost impossible to depict the alarm and excitement which followed. Panama 
has always been considered exempt from the mighty natural convulsions which are 
experienced almost periodically in the countries through which the giant Cordillera 
stretches its mountainous and volcanic ridges. That the shocks this morning were of 
exceptional violence appears to indicate a terrible calamity in some of those districts— 
and in all probability in the north—rather than a possibility that the old-time freedom 
of the Isthmus from earthquakes is about to disappear, and that henceforth we are 
to be subject to such dangerous and fearful visitations as those which on that morn¬ 
ing threatened the city with ruin. 

The amount of damage done can not as yet be estimated, but it must amount to at 
least $250,000. The municipal building and assembly rooms, under which the Cas- 
cada is situated, were much damaged. The whole of the massive balcony fell bodily 
into the square, dragging with it the roof and all adjacent timber. 

The cathedral also"suffered severely. Almost the whole of the ornate pediment, 
composed of heavy blocks of masonry, fell through the roof or onto the steps lead¬ 
ing to the principal entrance. Every arch in the nave is cracked and split, and large 
stones and pieces of cement have fallen from them. The side aisles are also seriously 
damaged, and an expenditure of at least $50,000 will be required to restore the build¬ 
ing. The roof of the assembly room will be repaired at any early date, Governor 
Borbua having acted with remarkable celerity and commenced work at once in order 
that the archives and furniture may not be exposed to damage from the rain. 

Private houses damaged are innumerable, and owners as yet fail to form a correct 
idea of the losses they have incurred. The walls of the canal office are cracked in 
several places, and the edifice requires strengthening. No estimate of damage can 
be made, but an expenditure of several thousand dollars must be incurred to render 
the building as safe as it was before the shock. 

The ruins of buildings destroyed by fire are unfortunately too conspicuous in the 
center of the city. Their danger has frequently been pointed out, and the earthquake 
has now accentuated the peril consequent on their being allowed to remain as here¬ 
tofore. Masses of these ruins have fallen down, and gaping cracks prove the neces¬ 
sity that they should be torn down. Outside the city a number of houses have 
suffered. The tower of Malambo Church has fallen, and a piece several yards square 



70 


INTEROCEAN1C CANAL. 


of the roof of Santa Ana Church has tumbled in. The crash among glassware and 
bottles has been universal, Mr. Brakemeier alone being a loser to the extent of $2,000 
from this cause. General Aizpuru’s house, in the Calle Real, has suffered severely, 
as has also that of Don Manuel Hurtado, in front of the Government house. Others 
who have suffered damage are Senores Antonio Jimenez, Agustin Clement, Jos6 
Manuel Casis, Barsallo, and the Grand Hotel, but the full extent of the damage done 
will not be known until the investigating committee has concluded its labors. 

Several hours have now elapsed and there has been no repetition of the shocks. 
It may therefore be confidently anticipated that they will not be repeated. 

The Pacific Mail steamship Clyde arrived from San Francisco on the night of the 6th. 
The earthquake was severely felt on board. Passengers declared that it appeared as 
if the vessel were lifted bodily from the sea and allowed to fall back. 

Thanks to the kindness of Mr. J. B. Stearns, general manager of the Central and 
South American Cable Company, we are able to inform our readers that the offices 
at Buenaventura, in Cauca, and San Juan del Sur, in Nicaragua, announce that no 
shock has been felt in either of those ports. The cable is working excellently and 
gives no sign that a general volcanic disturbance has taken place. 


The effects of the earthquake along the railroad have been most marked. The 
stone abutments of several of the bridges have been cracked and split, and the earth¬ 
work has sunk in a half a dozen places. Gangs of men were put at work on Thursday 
so that traffic might be resumed as usual at the earliest possible day. Mr. Woods 
and his subordinates have been active and energetic as usual, and cars were busily 
employed loading ballast to fill the sunken places, while lumber was being cut and 
prepared to support the short bridges which have been weakened, as already men¬ 
tioned, through the cracking of the abutments. 

All along the railroad track the earthquake was severely felt. At Emperador, 
Gatun, Matachin, and all the canal stations much alarm was created. 

In several places where the direct action of the shock appears to have made itself 
most strongly felt the rails were curved as if they had been intentionally bent. 

Mr. Woods, general superintendent of the railway, went across the same morning 
and returned as far as Bailamona in the afternoon. Neither train crossed in the after¬ 
noon. The Panama train stopped on this side of Bailamona bridge and the passen¬ 
gers and their baggage were transferred to hand and push cars, and thus conveyed 8 
miles over the road to Bohio Soldado—the farthest point the train from Colon could 
reach. 

The earthquake created great alarm in Colon. The freight house was damaged, 
and it was rumored that one or two were killed, but no certain information on this 
point has been obtainable. It is known, however, that two gentlemen broke their 
legs through jumping from the upper stories of houses. 

The telegraph wire was down during the early part of the day, but communication 
was reestablished at about 4 p. m. 

The sea was remarkably calm at Colon at the time of the severe shock, thus tend¬ 
ing to prove that the earth motion has not extended, as at first supposed, to the 
West Indies. 

The passengers and mails per Royal Mail steamer Don could not come across yes¬ 
terday, so that the Lima , after being delayed a day, had to leave for the south with¬ 
out them. 


[Daily Star and Herald, September 8.] 

Mother Earth on the Isthmus has not as yet returned to her ordinary quiescent 
condition. The severe shock of the morning of the 7th has been followed by several 
of less intensity, but which do not appear to make their effects felt over such a wide 
area. On Thursday afternoon several vibrations were experienced in different locali¬ 
ties which were not felt in Panama. 

At 11.30 p. m., on the 7th, a sharp shock alarmed the whole city, and drove the 
people from their houses to the squares. Hundreds of ladies, accustomed to every 
convenience and comfort, preferred to pass the night on mattresses, couches, and 
chairs in the public plazas to running the risk of being crushed to death in the 
houses. The inconveniences of the situation they thus accepted were obvious to the 
less timid, who walked from one square to another to see these temporary and 
uncampaign-like encampments. 




INTEROCEANIC CANAL. 71 

A slighter shock occurred at about 3 in the morning, but fortunately neither it nor 
its predecessor added further ruin to that already incurred in the city. 

All the shocks have been felt on the islands in the bay and some houses have suf¬ 
fered at Taboga. 

La Chorrera has been very unfortunate. The church and the cemetery are a mass 
of ruins and a number of houses have fallen. A bakery took fire and it and the 
adjoining house were totally destroyed by fire. 

Between Gavilan and Punta Mala, in the vicinity of this city, a crevasse has 
opened which is 10 meters in width. 

Some of the ruinous walls are being taken down, but there are several yet standing 
which are a permanent menace to adjoining properties and the lives of their inhabi¬ 
tants. 


[Colon correspondence Daily Star and Herald, September 9.] 

On the morning of September 7, at about 3.15, the residents of Colon were aroused 
from their peaceful slumber by the earthquake shock which has caused so much 
alarm and so considerable damage to the whole Isthmus. The duration of the shock 
was fully sixty seconds and was so severe that the whole populace rushed from their 
domiciles into the streets as rapidly as their feet could carry them. 

The greatest alarm prevailed. About half an hour afterwards another shock was 
felt, but much lighter than the first. The sensation produced by the first and more 
violent shock was that the whole town was about to sink into the bowels of the 
earth. No very considerable damage was done Several buildings were more or less 
damaged, including the French consulate, the house of Mr. F. R. Cowan, the Panama 
Railroad freight houses, and the wharves, the International Hotel, some smaller 
tenements in the rear of the town in the alley known as Cash street. One of the 
latter, built of brick and wood in the style known as brick noggin, was wrecked com¬ 
pletely, and one unfortunate occupant, a native, was killed. Two others, one a French¬ 
man and the other a bookkeeper for Messrs. Isaacs & Asch had each a leg broken 
in their haste to escape. The former will have to submit to the painful operation of 
amputation. 

A deep fissure was opened in the earth from the south end of the freight house for 
a distance of about 400 feet along the walk leading in the direction of the ice houses. 
Many buildings were moved slightly from their foundations, but on the whole 
remarkably little damage was done. On board the vessels in the harbor the shock 
was also felt very severely. 

The losses sustained were, principally in the breakage of bottles in the various 
stores and shops, and the smashing of crockery, mirrors, etc,, in private residences. 
This is pronounced the most severe shaking up ever before experienced in the his¬ 
tory of the country since the discovery and conquest, but on the whole the town has 
escaped without serious injury. On the 7th instant, about 1 p. m., another much 
slighter shock was felt, and during the night of the same day two more slight dis¬ 
turbances were reported. The people of the town have become quite alarmed and 
quite demoralized by these events, many rushing to the churches and calling upon 
God for protection and deliverance. If the result proves beneficial to the moral tone 
of the city, the tonic, although severe, may not be regretted. 

It may be of meteorological interest to observe that the sea at the time remained 
here calm, the atmosphere quite clear, and the stars and waning moon remarkably 
brilliant. Soon after, say about 4 o’clock, a slight fog wafted from inland. No rain fell. 
All day an ominous calm prevailed, without rain, with fluctuating barometer and 
excessive heat, which led many to fear a return of the shocks during the night of the 
7th, and few slept. But with the slight exceptions noted all remained quiet. 


Another correspondent writes from Colon: 

“At about 10 minutes past 3 this morning we experienced the most horrible earth¬ 
quake that I ever felt in my life. The damage done I can not estimate. A German 
employed as bookkeeper by Messrs. Isaacs & Asch threw himself out of the window 
and broke his leg, and a colored man followed his example, with a similar result. 
Two men have been killed, one of them being buried under a falling roof. The 
whole of the made ground between the wharves and the lagoon is split in a number 
of places. 

“A number of houses have suffered severely. . Some have fallen down bodily. 
Number four mole and the freight house has been damaged.' All here think the 
motion lasted at least one minute, and that it moved from the southeast toward the 
northwest.” 




72 


INTEROCEANIC CANAL. 


[Daily Star and Herald, September 11.] 

A slight earthquake shock occurred on the morning of the 9th, a little before 5 
o’clock. Much alarm was naturally created, but fortunately no damage was done. 
The frequent repetition of these movements causes a painful and uneasy feeling 
among the populace. A number of families passed the night on board the vessels in 
the bay and many in the public squares, and on Saturday a great many occupied 
the light cane houses on the outskirts of the city and at the Savana. 

The same shock was lightly felt in Colon and along the railroad track. No damage 
was done and work was continued on the houses injured by the shock of the 7th 
instant. 

All day on Saturday no shock was felt and the night passed quietly. At midday 
on Saturday there was a marked change in the atmosphere, and, with a refreshing 
shower which fell, the murky, sultry air of the previous days entirely disappeared. 

The rumor of a volcanic eruption at the town and fort of Chagres is pronounced 
entirely false. Thoroughly reliable persons were there at 1 p. m. on Saturday and 
reached Colon the same evening. They report the earthquake to have been felt 
there, and that the earth had cracked slightly in two or three places. Beyond this 
no damage was done. 

The shocks have been lightly felt on board the vessels in the bay, but they have 
experienced absolutely none of the tidal-wave effects which so frequently accompany 
widespread and powerful convulsions. 

Passenger and freight trains will run over the road to-dav.as usual, as it is believed 
‘all the breaks will have been thoroughly repaired last evening. 

The earthquake destroyed the little church at Cruces and damaged a few houses. 

The rumors of a volcanic eruption at Chagres are entirely without foundation. 
The earthquake was felt there, did some little damage, and opened a few cracks in 
the ground. 

A cablegram received from Mr. Scrvmser, the president of the Central American 
Cable Company, announces that in New York it was known the Colon cable was 
broken and that nothing had occurred in Cuba and the other islands. 


[Daily Star and Herald, September 12.] 

A commission of canal employees left Panama on Sunday afternoon and proceeded 
to Chagres to inspect the ground where the volcanic eruption is said to have taken 
place. A photographer accompanies them in order to obtain exact representations 
of any physical changes which may have occurred. The principal members of it are 
MM. Canel, Alvo, and Canell. It is believed they will be absent about a fortnight, 
as they have to examine a wide field. 

The rumors of the volcanic eruptions near Chagres and Cruces are declared to be 
entirely false by people arrived from there. One or two persons declare, however, 
that at 20 miles from Chagres, in the direction of “the coast,” a small mud volcano 
has been observed, but these statements are as untrustworthy and false as many 
which have been set current within the past few days. 

The truth of the matter appears to be that the repeated shocks have settled the 
loose alluvial soil, and that subsidence has occurred in several places, leaving fissures 
in some, and in others ejecting the thin mud formed on the lower strata by the per¬ 
colation of water. All the fissures observed so far present the same characteristics, 
and appear to be formed in the manner described and not by volcanic rents originat¬ 
ing in the bowels of the earth. 

The bridges on the railroad are now fully repaired, and freight and passenger 
trains crossed as usual yesterday. 

More rain is falling at Colon and on the other side of the Isthmus than on the 
Panama side. 

Three old and valueless ranches fell at Gatun when the severe shock of the 7th 
took place. A beam from one of them struck and instantly killed a poor woman, 
who was asleep. 

A number of people have walked, ridden, and canoed through the center of the 
Isthmus in order to discover the supposed-volcanic center. Their labor has been 
valueless, and all have returned convinced that no excessively severe motion has 
been experienced in any part. No loss of life has occurred, save the three cases we 
have reported. 



INTEROCEANIC CANAL. 


73 


» 

• [Daily Star and Herald, September 13.] 

The earthquake of the 7th instant was felt at the Pearl Islands in the bay. At 
San Miguel one of the walls of the church fell in, and the inhabitants took the saints 
nut and carried them in procession in the hope of preventing the repetition of the 
convulsion. They were panic-stricken. A correspondent writes that the earth con¬ 
tinued moving for five minutes, but this must be incorrect. 

At Donoso, Govea, and Rio Indio a number of shocks have been felt, and the peo¬ 
ple have been much frightened. At Miguel la Borda, 35 miles from Colon, in the 
direction of Bocas del Toro, the tide rose to an unusual height and flooded some of 
the houses, which are built on the beach almost on a level with the sea. The earth 
is said to have sunk in about a dozen places, and that cattle have been lost from this 
cause. The governor of the district writes officially that several boiling springs have 
suddenly appeared, some of which throw hot water to a considerable height. 
Although official, this report lacks confirmation. 

Many people believe they felt shocks in Panama during the night of the 11th 
instant, but the majority declare no movement took place. Overexcitement in 
many cases conduces the belief that the earth is trembling, and the least sound, such 
as a heavy cart passing through the streets, is at once converted by the excitable 
into the commencement of a catastrophe. 

A number of houses in Colon have suffered. A list is being drawn up. The heavy 
stone offices of the canal company have been badly cracked, and the employees are 
removing the desks, etc., to another building. The International Hotel, one of the 
largest buildings in Colon, has been somewhat damaged, but the trivial nature of the 
injury in such an extensive edifice seems to prove that good brickwork can resist 
movements which seriously injure houses which have been cheaply constructed. 
The moles in front of the freight house and the made ground at the back of it show 
signs of the movement, but the heavy stone walls of the building, although cracked 
in some places, are sound and good, while the iron trestlework which sustains the 
roof and holds the walls together is as tight and plumb as the day it was put together. 
Many frame houses have sagged over in different directions. The majority of these 
houses were never remarkable for symmetry; now they zigzag one way and the other 
and give the town a most peculiar appearance. It must be remembered there are a 
number of frame buildings in Colon which were run up as the earth was dumped 
into the sea to form the spit on which the town stands, and that consequently it is 
not surprising if the slightest shake should affect these frail wooden structures which 
have been exposed during nearly thirty years to the vicissitudes of the variable 
tropical climate. 

The bronze statue of Christopher Columbus was shaken free from the stone pedestal 
on which it stands, and moved about 4 inches from its former location. It can be 
readjusted at slight cost. 

At 6 a. m. yesterday the rain was pouring down in torrents in Colon. 

The Harrison steamer Mediator has arrived at Colon, and reports that a slight shock 
of earthquake was felt in Cartagena on the morning of the 7th. No damage was 
done. Letters from there dated the 9th scarcely mention the occurrence, thus prov¬ 
ing the little importance attached to it. 

Letters have been received from the towns of La Villa, Chitre, Macaracas, and 
Nata, all in this State, announcing that several shocks have been felt, but that the 
material of which the houses are built—bamboos and adobes—resisted the move¬ 
ments and have suffered no damage. At La Villa the bells in the church rang several 
times. The people do not appear to have been so alarmed as they have been in other 
parts of the Isthmus. 


[Daily Star and Herald, September 14.] 

Messrs. Schuber Brothers’ steamer Cargador, from ports in the northern depart¬ 
ments of the State of Panama, arrived yesterday, reports that repeated earthquakes 
have been felt, but that no damage to life or property has followed. 

The canal commissioners sent to examine reported volcanic effects in the center 
of the Isthmus have telegraphed that they are unable to find traces proving that the 
shocks have been sharper there than anywhere else in the State. 

Two or three slight tremblings were experienced in this city during the night of 
the 12th, but they caused no alarm. Many people are returning to their houses. 


O 



LB Je '06 


































